Media playback is unsupported on your device Media caption LIVE: Kenyan president briefing on attack 
 
 Kenyan forces are securing the Nairobi shopping centre attacked by suspected al-Shabab militants, as the stand-off enters its fourth day. 
 
 A senior police source said early on Tuesday the operation was "over", however journalists at the scene have reported sporadic gunfire at the mall. 
 
 There has been no official confirmation the siege is over. Kenya's president is expected to make a statement shortly. 
 
 At least 65 people have been killed, including three soldiers. 
 
 The Kenyan Red Cross says 51 people are still missing, and the BBC's Gabriel Gatehouse says mortuaries in the capital are expecting to receive more bodies. 
 
 Al-Shabab militia Name means "The Youth" in Arabic 
 
 Controls large areas of Somalia 
 
 Formed as a radical offshoot of the Union of Islamic Courts in 2006 
 
 Include foreign jihadists 
 
 Has launched cross-border raids into Kenya, Uganda 
 
 Estimated to have 7,000 to 9,000 fighters 
 
 Announced merger with al-Qaeda in 2012 Q&A: Who are Somalia's al-Shabab? 
 
 There are reports that part of the roof at the Westgate shopping centre has collapsed, following a fierce blaze on Monday. 
 
 The Somali Islamist al-Shabab movement said it had carried out the attack in retaliation for Kenyan military operations in Somalia. 
 
 Somali Prime Minister Abdi Farah Shirdon has said that those behind the attacks "must be held accountable." 
 
 Meanwhile, Kenya's foreign minister said "two or three" Americans and a British woman were among the attackers. 
 
 In an interview with the US TV programme PBS Newshour, Amina Mohamed said the Americans were 18 or 19 years old, of Somali or Arab origin, and lived "in Minnesota and one other place". 
 
 She said the Briton was a woman who had "done this many times before". 
 
 Ms Mohamed appeared to contradict earlier comments from Kenya's interior minister, who suggested that all the attackers were men - though some may have been dressed as women. 
 
 Ms Mohamed's remarks have fuelled media speculation about the possible involvement of Samantha Lewthwaite, the widow of one of the men who carried out attacks on London's transport system on 7 July 2005. 
 
 Why are they doing this to such innocent people - those attackers are not only enemies to non-Muslims but to humanity Abdirizak Nur Ibrahim, Kenyan Somali Fear of reprisals 
 
 British officials said they would not be drawn on the identity of the attackers while investigations continued. 
 
 Mosque leaders in Minnesota have condemned the violence, saying the attacks had nothing to do with Islam. 
 
 Unanswered questions 
 
 The Kenyan security forces are continuing to comb the shopping centre to flush out the last of the militants. 
 
 The interior ministry said security officials were in "mop-up operations" and that "we're very near the end", while the police said they were defusing explosives planted in the area. 
 
 The BBC understands from official sources that six of the attackers have been killed - three on Monday and three since midnight. 
 
 The government said there were 10 to 15 militants involved in Saturday's attack, and it is not yet clear how the rest are accounted for. 
 
 Al-Shabab has made counter-claims on social media that it is still in contact with fighters in the shopping mall, and they still have hostages. 
 
 The government has said it has no indication that there are any captives. 
 
 Officials said earlier that 10 people had been arrested in connection with the attack. 
 
 Image caption Al-Shabab say this picture, which circulated on social media on Monday, shows their fighters in the shopping centre 
 
 'Three heroes' 
 
 Militants stormed the Westgate centre on Saturday, throwing grenades and firing on shoppers and staff. 
 
 At least 18 foreigners are among the dead, including six Britons, as well as citizens from France, Canada, the Netherlands, Australia, Peru, India, Ghana, South Africa and China. 
 
 The interior ministry said on Tuesday that three soldiers had succumbed to their injuries, and eight were still being treated. "We've lost three heroes," the ministry said on its Twitter account. 
 
 Nearly 200 people were wounded. 
 
 President Barack Obama called the attack a "terrible outrage" and said the US was providing all the co-operation it could to Kenya. 
 
 Thousands of Kenyans have been responding to appeals for blood donations. 
 
 Al-Shabab, which is linked to al-Qaeda, has repeatedly threatened attacks on Kenyan soil if Nairobi did not pull its troops out of Somalia. 
 
 There are about 4,000 Kenyan troops in the south of Somalia as part of an African Union force supporting Somali government forces. 
 
 Al-Shabab is fighting to create an Islamic state in Somalia. 
 
 Despite being pushed out of key cities in the past two years, it remains in control of smaller towns and large swathes of the countryside. 
 
 UN special representative for Somalia Nicholas Kay called on Tuesday for a fresh surge in African troops to Somalia to counter an estimated 5,000 al-Shabab fighters, Reuters news agency reported. ||||| Media playback is unsupported on your device Media caption Karen Allen in Nairobi: "Kenya will never be the same again" 
 
 Kenyan officials say they are in the final stages of bringing to an end the deadly stand-off with suspected al-Shabab militants in Nairobi. 
 
 Explosions and heavy gunfire were reported earlier as soldiers stormed the Westgate shopping complex. 
 
 Three "terrorists" were killed and soldiers are continuing to comb the building floor by floor "looking for anyone left behind", officials said. 
 
 The Kenyan Red Cross has told the BBC that 63 people remain unaccounted for. 
 
 'Under control' 
 
 Analysis A number of countries are believed to have offered assistance to the Kenyan authorities currently dealing with the siege at the Westgate Mall. Kenya is seen as a largely pro-Western country in a strategically important continent that is facing growing instability from the threat of Islamic extremism. Western interests in Kenya have also been targets in the past - most notably the 1998 attack on the US embassy in Nairobi carried out by al-Qaeda. However, at present, Kenya's forces are taking the lead in the hostage crisis. If there is any involvement by foreign nations, it's likely to be in a purely advisory role. It has already been reported that Israeli "security specialists" are on the ground in Nairobi giving advice, although this has not officially been confirmed. Even if foreign forces are giving advice or even more, the Kenyan authorities are unlikely to want to give the impression that they cannot deal with this crisis themselves. 
 
 The official death toll stands at 62 and more than 170 have been injured. There are fears the death toll will rise further. 
 
 British Defence Secretary Philip Hammond said that his best estimate was that six Britons had been killed. 
 
 The Somali Islamist al-Shabab movement has said it carried out the attack in retaliation for Kenyan military operations in Somalia. 
 
 "The terrorists could be running and hiding in some stores, but all floors now are under our control," Kenyan Interior Minister Joseph Ole Lenku said. 
 
 "There is no room for escape." 
 
 He told the BBC late on Monday that the operation would continue overnight, but stressed it was in its final stages. 
 
 The minister added that "it is very unlikely that there are any hostages" left in the complex. 
 
 Flames 
 
 The BBC's Gabriel Gatehouse, who is at the scene, says there is still no clear picture of what is going on inside; officials have said forces are in control of the mall but have not said if they have arrested or killed all attackers. 
 
 As night fell on Monday, flames and thick smoke continued to rise from the complex. 
 
 The Kenya Defence Forces said the fire had been started by "terrorists to distract the ongoing operation", and that the blaze was being managed by firefighters. 
 
 President Barack Obama said the US was offering its full support to the Kenyan authorities. 
 
 Kenya is one of the largest recipients of US security assistance in sub-Saharan Africa, with much of that aid focused on counter-terrorism. 
 
 Media playback is unsupported on your device Media caption President Obama says the US stands with Kenya 
 
 The BBC's defence correspondent Jonathan Beale says the US is likely to have responded to the crisis by sending one of its Foreign Emergency Support Teams (Fest). 
 
 But there was no suggestion they are directly involved, our correspondent says. 
 
 The KDF said 10 bodies had been retrieved from the building in the last 24 hours. More than 200 civilians have been rescued, 65 of whom remain in hospital. 
 
 Eleven KDF soldiers were injured during the operation, it said. 
 
 Earlier, police used tear gas to disperse crowds of onlookers gathered close to the Westgate Centre. 
 
 The Interior Ministry has been issuing regular warnings for people to stay away for their own safety. 
 
 Image caption Thick black smoke started billowing from the building shortly after blasts were heard 
 
 Image caption The Kenyan interior minister said security forces were gaining an advantage over the militants 
 
 Image caption Kenyan police officers took position around the Westgate Shopping Centre 
 
 Image caption Police fired tear gas to try to disperse crowds of onlookers near the centre. 
 
 Security has also been stepped up at entrance and exit points across the country, with "more than 10 individuals" arrested in relation to the attack, the ministry said. 
 
 It did not specify when or where the arrests were made, but media reports from Kenya said the suspects were detained at the Jomo Kenyatta International Airport. 
 
 Repeated threats 
 
 More than 1,000 people were inside the mall complex when the attack began on Saturday. 
 
 Dr Sunil Sachdeva, a dentist who runs a clinic inside the mall, described the scene as the attack unfolded. 
 
 Al-Shabab militia Name means "The Youth" in Arabic 
 
 Controls large areas of Somalia 
 
 Formed as a radical offshoot of the Union of Islamic Courts in 2006 
 
 Include foreign jihadists 
 
 Has launched cross-border raids into Kenya, Uganda 
 
 Estimated to have 7,000 to 9,000 fighters 
 
 Announced merger with al-Qaeda in 2012 Q&A: Who are Somalia's al-Shabab? 
 
 "There was a tent where a cookery competition for children was carrying on and there were bodies lying under there," he told the BBC. 
 
 "There's a very famous radio presenter in Kenya, she was shot. The scene was carnage and there was a guy lying right in the corner. He was cut to shreds." 
 
 Prominent Ghanaian poet Kofi Awoonor - who was attending a literary festival in Nairobi - also died, as did a Chinese woman. 
 
 French, Dutch, South African, Indian and Canadian nationals are also among the foreigners confirmed killed, along with a dual Australian-British national. 
 
 Thousands of Kenyans have been responding to appeals for blood donations. 
 
 Al-Shabab, which is part of the al-Qaeda network, has repeatedly threatened attacks on Kenyan soil if Nairobi did not pull its troops out of Somalia. 
 
 There are about 4,000 Kenyan troops in the south of Somalia, where they have been fighting the militants since 2011 as part of an African Union force supporting Somali government forces. 
 
 Al-Shabab is fighting to create an Islamic state in Somalia. 
 
 Despite being pushed out of key cities in the past two years, it still remains in control of smaller towns and large swathes of the countryside. ||||| Gunshots rang out from an upscale mall in Kenya's capital Wednesday morning, a day after the country's president said his military had “ashamed and defeated” Al Qaeda-linked terrorists in an apparent end to a four-day standoff and hostage situation inside the popular shopping center. 
 
 Government spokesman Manoah Esipisu told The Associated Press the shots came from Kenyan forces going room to room in the large Westgate Mall, firing protectively before entering unknown territory. 
 
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 But a top security official, speaking on condition of anonymity because of the sensitivity of the information, said even around the time President Uhuru Kenyatta told the nation in a televised address that "we have ashamed and defeated our attackers" on Tuesday night, three shots rang out at the mall. 
 
 He said Kenyan authorities are still trying to determine where those shots came from. 
 
 Kenyatta said in a national address Tuesday that 61 civilians and six security officers were killed in the violence at Nairobi’s Westgate Mall, and called for three days of national mourning beginning Wednesday. 
 
 Kenyatta added that three floors of the mall collapsed and that there are "several bodies still trapped in the rubble, including the terrorists." 
 
 FBI investigators are now waiting for forensic evidence, including fingerprints taken from inside the mall as well as dental records, to verify claims that some of the attackers were Americans, a federal law enforcement source told Fox News. 
 
 Kenya's foreign minister, Amina Mohamed, claimed in a television interview Monday that two or three Americans and one Briton were among those behind the attack. 
 
 Amina Mohamed said in an interview with PBS' "NewsHour" program that the Americans were 18 to 19 years old, of Somali or Arab origin and lived "in Minnesota and one other place" in the U.S. The attacker from Britain was a woman who has "done this many times before," Mohamed said. 
 
 On Sunday, Homeland Security and the FBI sent out a joint bulletin to federal, state and local law enforcement agencies after the militants stormed the mall a day earlier, sources told Fox News. The bulletin emphasized the continuing threat of al-Shabab -- the Somali-based terror group who claimed responsibility for the attack -- but did not advise any changes to security inside American malls. 
 
 Earlier Tuesday, al-Shabab said its fighters were still holding out inside the mall, despite claims from Kenya that said otherwise. 
 
 “There are [a] countless number of dead bodies still scattered inside the mall, and the mujahedeen are still holding their ground,” al-Shabab wrote on its Twitter account. 
 
 In a Tweet Wednesday from an account believed to be genuine, al-Shabab also claimed that Kenyan government forces used explosives in carrying out "a demolition" of the building, burying 137 hostages. 
 
 The group also claimed that "having failed to defeat the mujahideen inside the mall, the Kenyan govt disseminated chemical gases to end the siege." 
 
 The group’s previous Twitter accounts had been shut down, according to Reuters. 
 
 Authorities said Tuesday they were involved in a final push to clear out the remaining attackers, who were holding hostages. But with the building cordoned off and under heavy security, it was not possible to immediately verify the assertions. 
 
 "Troops now in mop up operations in the building," a Kenyan police tweet said on Tuesday. On Monday night, Kenyan officials said they were “in control,” according to Reuters. 
 
 Explosions and more gunfire were heard coming from the mall Tuesday, while a plane and helicopter circled over the building. 
 
 Kenyan officials say three soldiers have died and eight others were injured in the assault on Tuesday. Federal law enforcement sources told Fox News that the terrorists used explosives. 
 
 While the government announced Sunday that "most" hostages had been released, at least 10 were still being held earlier Tuesday by a band of attackers described as "a multinational collection from all over the world," a security expert with contacts inside the mall told The Associated Press. 
 
 On Monday, sources told Fox News that Kenyan security forces battled what was believed to be 10 to 15 gunmen hiding on the top floor of the mall for several hours, neutralizing most of them. 
 
 A government official said Tuesday that Nairobi's morgue is also preparing for the arrival of a large number of bodies from the mall. Morgue employees were dressed in smocks early Tuesday, though no bodies had been delivered. A city resident whose brother took part in the military operation inside the mall said there were many dead bodies still inside. 
 
 Both the government official and the Nairobi resident insisted their names not be used so they would not face retribution from officials. 
 
 A U.S. Embassy vehicle, identifiable by its numbered diplomatic license plate, arrived at the morgue on Tuesday. American officials have not confirmed the deaths of any U.S. citizens in the mall attack, but it appeared possible the Americans who visited the morgue could have been seeking information about one of the bodies inside. 
 
 Mohamed's statement about the alleged nationalities of the attackers also fueled speculation that a 29-year-old woman named Samantha Lewthwaite was involved in the attacks. Lewthwaite, a native of Buckinghamshire who converted to Islam at age 15 and was believed by Western intelligence agencies to be in East Africa, is the widow of Germaine Lindsay, one of the perpetrators of the July 7, 2005, suicide attacks on London's transport system during the morning rush hour. British security sources contacted by Reuters said that Lewthwaite's involvement in the attack was possible, but cautioned that no definitive information had been received. 
 
 In the initial Saturday attack, the militants specifically targeted non-Muslims, and at least 18 foreigners were among the dead, including six Britons, as well as citizens from France, Canada, the Netherlands, Australia, Peru, India, Ghana, South Africa and China. Five Americans were among the nearly 200 people wounded in the attack. 
 
 The al-Shabab terrorist group – which is estimated to have several thousand fighters -- grew out of the anarchy that crippled Somalia after warlords ousted a longtime dictator in 1991. Its name means "The Youth" in Arabic, and it was a splinter youth wing of a weak Islamic Courts Union government created in 2006 to establish a fundamentalist Islamic state in the East African nation. 
 
 Al-Shabab said it attacked the mall as retaliation for Kenya's involvement in a crackdown on Islamic militants in neighboring Somalia. 
 
 The Associated Press contributed to this report. ||||| The new images from the inside the Westgate Mall in Kenya are sobering: a family playing dead to avoid harm, shoppers escaping, and a child being carried to safety. More than 60 people died in the terrorist attack, most of them civilians. NBC's Ron Allen reports. 
 
 Kenya’s president Tuesday said security forces have killed five terrorists and arrested 11 suspects in connection with the horrific siege on a Nairobi shopping mall, bringing to a close four days of chaos and carnage. 
 
 After avoiding both gunfire and grenades, Bendita Malakia has finally arrived back home following her ordeal at the Kenya mall where terrorists killed dozens of civilians. She hid for five hours until an American security team showed up and rescued her and the group of people she was hiding with. NBC's Tom Costello reports. 
 
 The al Qaeda-linked attackers — believed by Kenyan officials to include “two or three Americans” and a British woman — staged a shooting massacre that killed some 61 civilians and 6 security officers and shattered countless lives. However, President Uhuru Kenyatta said he could not confirm reports of American or British involvement in the attack. 
 
 Kenyatta said that Wednesday will mark the beginning of three days of national mourning. Some 62 people have been operated on in the wake of the siege and remain in the hospital, he said. 
 
 His announcement Tuesday capped off hours of uncertainty, as security officials said that they had gained ground on the heavily-armed militants from the Somalia-based al-Shabaab while the al Qaeda-affiliated group claimed in an unverified Twitter post that they were “still holding their ground” inside the luxury Westgate complex. 
 
 Kenyatta added that three floors of the mall complex had collapsed and bodies remained in the rubble on Tuesday. 
 
 There are countless number of dead bodies still scattered inside the mall, and the Mujahideen are still holding their ground #Westgate — HSM Press Office (@HSM_PR) September 24, 2013 
 
 It also posted a security video image that it said showed its members "strolling around the mall." 
 
 Here are 2 of the Mujahideen inside #Westgate mall, unruffled and strolling around the mall in such sangfroid manner pic.twitter.com/bMG87AQOon — HSM Press Office (@HSM_PR) September 24, 2013 
 
 Al Shabaab regularly changes its Twitter handle as its accounts are frequently suspended. Earlier, Kenya's Interior Ministry had tweeted that security forces were "in control of Westgate." 
 
 During an address on state TV, Kenya's President Uhuru Kenyatta announced that security forces killed five terrorists and have arrested 11 suspects in connection with the horrific siege on a Nairobi shopping mall, assuring Kenyans and people around the world that "these cowards will meet justice." 
 
 Amina Mohamed, Kenya’s foreign minister, told PBS Newshour late Monday that American and British citizens of Somali or Arab origin were believed to be among the perpetrators “from the information that we have.” 
 
 She said the Americans were "young men, about between maybe 18 and 19" years old and lived in "in Minnesota and one other place." 
 
 However, a senior U.S. law enforcement official told NBC News that authorities had been unable to verify that Americans were involved, despite aggressive checks of travel records. 
 
 "That doesn't mean it's not true. We just have no information to go on," the official said. 
 
 A British woman was also involved, Mohamed said – fueling speculation that Samantha Lewthwaite, the widow of a suicide bomber who attacked London's transit system in 2005, was linked to the Kenya siege. 
 
 On the presumed al Shabaab Twitter account on Tuesday, the group denied that women were involved in the mall attack, suggesting it was a ploy by Kenyan officials to “curry favor” with the British government. 
 
 Prize-winning New York Times photographer Tyler Hicks described what he saw in the mall where so many innocent people were killed. "I could see how tense everyone was," Hicks said, describing the extreme care with which police entered the building where "everywhere you looked you would see another body." 
 
 “We have an adequate number of young men who are fully committed and we do not employ our sisters in such military operation,” the tweet from @HSM_PR said. 
 
 As the standoff wore on, the survivors' stories emerged. 
 
 Some of them took to Twitter: Kamal Kaur, a journalist for Radio Africa, chronicled the ordeal in a heartbreaking series of posts and said she could not stop thinking about a little boy who was shot instead of her own son. 
 
 The bullet missed her son by an inch, she wrote — “almost had his head blown off” — then bounced off a wall and struck and killed the other boy. 
 
 “Image of the boy I was trying to save but got shot instead of my son keeps swimming in front of my eyes,” Kaur wrote, in posts collected by The Independent, a British newspaper. “How do I sleep after seeing that?” 
 
 The journalist spoke of dried blood in her hair, dead bodies and wailing victims. 
 
 Al Shabaab was blamed for two bombings in the capital of Uganda two years ago that killed 75 people, and attacks against the government of Somalia. The group has tried to entice westerners to join, but the Somali-American community has made efforts to stop their recruitment. NBC's Pete Williams reports. 
 
 “Bodies of children were everywhere,” she wrote. “Children. Innocent little children. Holding on to me asking where their mummies were.” 
 
 Kaur’s colleague and friend Ruhlia Adatia, six months pregnant, was killed in the siege. Kaur wrote on Twitter about breaking the news to her own children about Adatia, known to them as Ruhlia Auntie. 
 
 “I still haven’t told my children that their Ruhila Auntie is no more. I don’t know how to. I can’t. They’re still in shock & wounded.” 
 
 Dorkas Moingee, a woman who was inside the mall at the time of the attack, described to TODAY the initial shock of the siege and the harrowing panic that followed. 
 
 Kenya's Foreign Minister continues to insist that two to three Americans are among the attackers in the Nairobi Westgate mall. NBC's Ron Allen reports. 
 
 “When I first head the gunshots I wasn’t sure that they were gunshots,” Moingee said. “I actually thought it was an earthquake.” 
 
 “There were hundreds of gunshots that I heard and that’s when everyone ran for cover,” she added. 
 
 Five Americans were reported injured in the mall attack, including a San Diego woman. Among the dead were four Britons and a Canadian diplomat, and British Prime Minister David Cameron said: “We should prepare ourselves for further bad news.” 
 
 Al Shabaab is an Islamist terrorist force that grew out of the anarchy that crippled Somalia after warlords ousted a longtime dictator in 1991. Its supporters include many Somalis living in other countries including the U.S. and Britain. 
 
 Kenya has sent troops to Somalia as part of an African Union force trying to stabilize the country, which was long without a functioning government, and push back al Shabaab. 
 
 The United Nations envoy for Somalia called on Tuesday for additional African troops to counter al Shabaab, which he said numbered some 5,000 people and posed an international threat. 
 
 Slideshow: Gunmen attack mall in Kenya Carl De Souza / AFP - Getty Images Gunmen stormed a crowded shopping mall frequented by Westerners in a brazen midday attack Launch slideshow 
 
 "Security remains the number one challenge, the control and defeating of al Shabaab is key to this," Nicholas Kay, U.N. special representative for Somalia, told reporters in Geneva, Reuters reported. 
 
 President Obama told the United Nations General Assembly on Tuesday morning that the attack “indicates the dangers that remain” in the global fight against terrorism. 
 
 Obama told dignitaries and envoys from some 200 member states that al Qaeda has broken into regional networks and militias, which presents “serious threats to governments, diplomats, businesses and civilians across the globe.” 
 
 NBC News' Mary Murray and Sohel Uddin contributed to this report. Reuters also contributed. 
 
 
 
 NBC Terror Analyst Roger Cressey says that the Somali terror cell al-Shabaab could be using Americans in the Westgate mall attack to create "broad international appeal" that could increase donations to their organization. 
 
 Related: 
 
 This story was originally published on ||||| Are you in Nairobi? Send us your images and experiences, but please stay safe. 
 
 Nairobi, Kenya (CNN) -- Several gunmen remain inside a besieged mall in Nairobi, Kenya, two senior officials said, as a deadly standoff between Kenyan forces and terrorists stretches into a fourth day. 
 
 Kenya's Interior Ministry tweeted late Monday that authorities were in control of the Westgate Shopping Mall -- the latest in a series of social media posts from officials reassuring a nervous public that there was little chance of escape for any surviving Al-Shabaab gunmen who had terrorized the mall, killing at least 62 people. 
 
 "Taken control of all the floors. We're not here to feed the attackers with pastries but to finish and punish them," Kenyan police Inspector General David Kimaiyo said on Twitter. 
 
 But even as police stressed on Twitter that they were in charge of the situation, two senior Kenyan officials told CNN that gunmen -- including snipers -- were still inside the four-story mall. 
 
 It wasn't clear whether any hostages remained. The Kenya Red Cross said 65 people were missing after the attack. 
 
 Gunfire echoed from the mall sporadically during the day, sending journalists and aid workers scrambling for cover. Thick heavy smoke -- from a fire set by terrorists, according to Kenyan authorities -- billowed into the air much of the afternoon. 
 
 Kenya assault raises new fears about Somali recruitment 
 
 Three terrorists have been confirmed killed since Saturday, the Interior Ministry said Monday. Eleven Kenyan soldiers have been wounded, according to the Kenya Defence Forces. More than 200 civilians have been rescued, the military said. 
 
 Away from the mall, Kenyan authorities said they had arrested more than 10 people for questioning in connection with the attack, including at least four taken into custody at an airport. 
 
 Authorities urged law enforcement officers to closely scrutinize travelers' documents, and the country's Immigration Department said in a tweet that it had increased security at entry and exit points. 
 
 Surviving the Nairobi mall massacre: 'Just lucky' 
 
 Americans involved? 
 
 Kenyan Foreign Minister Amina Mohamed told "PBS NewsHour" that some of the attackers had come from the United States. She said they were originally from Minnesota and Missouri, PBS reported Monday. 
 
 "As you know, both the victims and the perpetrators came from Kenya, the United Kingdom and the United States," she said. "From the information that we have, two or three Americans, and I think so far I've heard of one Brit" as being among the attackers. 
 
 "The Americans, from the information we have, are young men, about between maybe 18 and 19, of Somalia origin or Arab origin," Mohamed told PBS. She offered no other specifics. 
 
 Her comments seemed to expound on those of Gen. Julius Karangi, chief of Defense Forces. 
 
 "We have an idea who these people are and they are clearly a multinational collection from all over the world," he told reporters in Nairobi. "This is not clearly a local event. We are fighting global terrorism here." 
 
 Before its Twitter account was suspended, Al-Shabaab issued a list of the names of nine people it said were among the attackers. It said three were from the United States, two from Somalia and one each from Canada, Finland, Kenya and the United Kingdom. 
 
 Sources within Al-Shabaab also told CNN that the nine names published on Twitter were among the alleged hostage-takers, but CNN has not been able to independently confirm that. 
 
 U.S. officials don't have any confirmation of Americans having been involved in the attack, according to Deputy National Security Adviser Ben Rhodes and another senior official. 
 
 Intelligence analysts are poring over electronic intercepts in an effort to verify the terror group's claims, two law enforcement sources told CNN. 
 
 The FBI also was looking into the claims, law enforcement officials told CNN. 
 
 "At this point we have no definitive evidence of the nationalities or identities of the perpetrators," State Department spokeswoman Jen Psaki said Monday. 
 
 In the past, federal officials and Somali-American leaders in Minneapolis have reported that Al-Shabaab has recruited young men there to go to Africa to fight. 
 
 U.S. President Barack Obama expressed condolences over the attack after a meeting on the sidelines of the U.N. General Assembly Monday. He didn't specify whether Americans had been involved, but he pledged U.S. support and described the situation as a matter of global concern. 
 
 "This, I think, underscores the degree to which all of us as an international community have to stand against the kind of senseless violence that these kinds of groups represent," Obama said. 
 
 The siege 
 
 The terrorist attack began at midday Saturday, Nairobi time, with an estimated 10 to 15 gunmen taking over the mall in what hospital volunteer Abiti Shah said witnesses told her was "like a Hollywood action scene." 
 
 "They just started firing in the air," Shah said, retelling the witness accounts. 
 
 A youth cooking competition was taking place at the mall at the time, and terrified shoppers fled for their lives as gunfire echoed through the building. 
 
 Witnesses said the gunmen went from store to store, shooting people, and then took hostages. 
 
 Survivor Bendita Malakia, a North Carolina woman who moved to Nairobi in July, told CNN affiliate WAVY that she took refuge behind the closed metal gates of a store with dozens of others. 
 
 The Kenyan spirit cannot be broken, says eyewitness resident 
 
 "While we were back there, you could hear them methodically going from store to store, talking to people and asking questions," she said. "They were shooting, screaming. Then it would stop for a while and they would go to another store." 
 
 Al-Shabaab has claimed that the attackers targeted non-Muslims and vowed they would not negotiate for the hostages' lives. CNN security analyst Peter Bergen said the terrorists apparently took hostages only to prolong the siege and win more media attention. 
 
 The dead 
 
 Most of the dead were said to be Kenyans. 
 
 Six British citizens, two French nationals, two Indians and two Canadians, including a diplomat, also died, their governments said. 
 
 Those killed include: 
 
 • Elif Yavuz, a senior vaccines researcher for the Clinton Health Access Initiative based in Tanzania. Yavuz, a Dutch national, was pregnant and expecting her first child in October, according to Julio Frenk, dean of faculty at the Harvard School of Public Health. "Elif was brilliant, dedicated, and deeply admired by her colleagues, who will miss her terribly," the Clinton family said in a statement. The Dutch Foreign Affairs Ministry confirmed a 33-year-old Dutch woman had been killed. 
 
 • A major African poet, author and Ghanian statesman, Kofi Awoonor, Ghana's president said. Awoonor received his Ph.D. from New York's Stony Brook University and was a professor of literature there in the 1970s. 
 
 • The nephew of Kenyan President Uhuru Kenyatta and the man's fiancee. 
 
 • A Peruvian doctor, Juan Jesus Ortiz, who had previously worked for the United Nations Fund for Children and lived in Kenya doing consulting work, the country's Foreign Affairs Ministry said. 
 
 • Sridhar Natarajan, 40, an Indian national and employee of a local pharmaceutical firm, and 8-year-old Paramshu Jain, the son of a bank branch manager, CNN sister network CNN-IBN reported, citing government officials in New Delhi. 
 
 The wounded 
 
 Kenyatta said more than 175 people had been wounded. Five were Americans, the State Department said Sunday. 
 
 Elaine Dang, 26, a University of California, Berkeley, graduate from San Diego, underwent surgery to her chest, arms and legs. 
 
 "I'm OK, I'm very grateful to be alive," she told CNN affiliate KFMB-TV 
 
 She said two friends died in the attack. 
 
 Al-Shabaab breaks new ground with complex Nairobi attack 
 
 The terrorists 
 
 The Somalia-based Al-Shabaab terror group had said on Twitter that it had sent the gunmen to the mall in retaliation for Kenya's involvement in an African Union military effort against the group, which is al Qaeda's proxy in Somalia. 
 
 Last year, the Kenyan military was part of a peacekeeping force that defeated Al-Shabaab forces to liberate the key Somali port of Kismayo. 
 
 Since Kenya launched attacks against Al-Shabaab in Somalia in 2011, the group has hurled grenades at Kenyan churches, bus stops and other public places. 
 
 The mall attack is the deadliest terror attack in Kenya since al Qaeda blew up the U.S. Embassy there in 1998, killing 213 people. 
 
 On Monday, Kenya's foreign minister told CNN it's clear that Al-Shabaab was not acting alone. 
 
 "This bares the hallmarks of al Qaeda. This is not just Al-Shabaab. In fact, the leaders are not Somali, as you may have heard. This was al Qaeda. It was a very well-coordinated effort, it was very well planned," Mohamed said. 
 
 But the attackers' national origins are irrelevant, she said. 
 
 "It doesn't matter where they come from. There are some Americans. There are some Brits. There are some others. It has nothing to do with the nationality of people," Mohamed said. "They are all evil and we must deal with them as such." 
 
 Al-Shabaab grew amid Somalia's lawlessness 
 
 The investigation 
 
 Lenku said that Monday's effort to roust the terrorists was a Kenyan operation, but government sources told CNN that Israeli special forces also were at the scene. 
 
 Kenyatta, the Kenyan president, vowed Sunday to punish those responsible for the attacks. 
 
 "They shall not get away with their despicable, beastly acts. Like the cowardly perpetrators now cornered in the building, we will punish the masterminds swiftly and indeed very painfully," he said. 
 
 U.S. Secretary of State John Kerry promised an American investigation. 
 
 Kenya bloodshed: World leaders react 
 
 "Obviously, it's an enormous offense against everybody's sense of right and wrong," Kerry said. "It represents the seriousness and the breadth of the challenge we face with ruthless and completely reckless terrorists, and we're going to pursue them." 
 
 Michael Pearson reported and wrote from Atlanta; Zain Verjee and Nima Elbagir reported from Nairobi. CNN's Arwa Damon, Becky Anderson, Lillian Lesposo, Holly Yan, Greg Botelho, Brian Walker, Jackie Castillo, David Simpson, Dominique Dodley and Kevin Conlon also contributed to this report.
– Is the siege of Nairobi's Westgate Mall finally near an end? Kenyan authorities say they believe all the hostages have been released, but journalists from the AP and Reuters heard yet more gunfire and explosions as the Kenyan military moved through the building. Officials say the military is going from floor to floor and room to room in the darkened building searching for surviving militants, the Los Angeles Times reports. Somalia's al-Shabab militant group tweeted early today that its fighters "are still holding their ground" and their captives are "still alive, looking quite disconcerted but, nevertheless, alive." In other developments: Kenya's foreign minister told PBS Newshour last night that two or three Americans were involved in the attack. She said they were of Arab or Somali origin, 18 or 19 years old, and had lived "in Minnesota and one other place" in the US. She said a British woman who had "done this many times before" was also involved, contradicting another minister's statement that all the attackers were men. Security officials and soldiers told Reuters that a white woman was among the attackers killed, though they couldn't confirm whether she was Samantha Lewthwaite, the al-Shabab-linked widow of a British terrorist. The State Department says that it is investigating reports that Americans were involved, but "at this point we have no definitive evidence of the nationalities or identities of the perpetrators," the Washington Post reports. Witnesses say most of the attackers were young and shouted to each other in English. British officials say they will not discuss the identity of the attackers while the investigation continues, reports the BBC. Officials say at least six attackers have been killed and around 10 more captured. The civilian body count stands at 62, but the Red Cross says 63 people are still unaccounted for. In Minnesota, home to America's largest Somali community, Muslim leaders refused to comment on reports that Somali Americans were involved in the attack but spoke firmly against extremism, the Star Tribune reports. The attackers "do not represent any religion, they do not represent any community, they do not represent any nationality," one imam said. "They are an organized group of criminals who have conspired to kill and destroy innocent lives. They are nothing but criminals. They are not ­Muslims."