CLOSE Scores of people were killed and many more were wounded in the shooting at a gay nightclub in Orlando, Florida. 
 
 Orlando police officers seen outside of Pulse nightclub after a fatal shooting and hostage situation on June 12, 2016 in Orlando, Florida. The suspect was shot and killed by police after 20 people died and 42 were injured. (Photo by Gerardo Mora/Getty Images) (Photo: Gerardo Mora, Getty Images) 
 
 A night of partying and dancing at Pulse, a gay nightclub in Orlando, turned into a killing ground and three hours of terror for early-morning revelers when a gunman opened fire around 2 a.m. ET inside the club, killing 50 people and wounding at least 53 in what is being called the worst mass shooting in U.S. history. 
 
 Here’a a rough timeline of the three hours from the time the gunman gained entrance to the club, Pulse Orlando, around 2 a.m. ET to the time authorities killed the assailant around 5 a.m. ET. (All times are Eastern standard time). 
 
 SIEGE BEGINS: 
 
 2:02 a.m. Shots ring out as a police officer working as a security guard engages in gun battle with assailant, Omar Mateen, 29, of Port St. Lucie, Fla., outside the Pulse Orlando nightclub around closing time, according to Orlando police chief John Mina. Mateen was armed with an AR-15-style assault rifle, a handgun and an unidentified device. 
 
 The gunman makes way into club, where more than 300 people were enjoying Latino night, and opens fire, causing chaos as patrons realize what is unfolding. Mateen fired an "unknown number of rounds," the police chief said. "There were numerous shots." Eyewitnesses said people on the dance floor and around the bar area dived to the floor, with some lucky enough to flee. 
 
 Jackie Smith, who was inside the club and says two friends were shot, told the Associated Press after release from Orlando Regional Medical Center: "Some guy walked in and started shooting everybody. He had an automatic rifle, so nobody stood a chance. I just tried to get out of there." 
 
 2:06 a.m. Mina Justice was sound asleep when, she told the Associated Press, she got a text from her son, Eddie, from inside the club. 
 
 “Mommy I love you,” the message said. “In club they shooting.” 
 
 CLOSE Mina Justice's 30-year-old son Eddie texted her from the Pulse nightclub when the shooting occurred. He said he ran into a bathroom with other patrons to hide and told her to call police. He then texted her: "He's coming, I'm gonna die." AP 
 
 2:09 a.m. About seven minutes after the first shot, the Pulse Orlando nightclub's Facebook page zapped out a chilling message: "Everyone get out of pulse and keep running." 
 
 2:17 a.m. @bjoewolf (Brandon Wolf), tweets: “Omg. Shooting at pulse. We hid in the bathroom. And we can’t find our friends." 
 
 Club goer Christopher Hansen who escaped the club, later told CNN, “It’s just shocking, I just saw bodies going down.” Hansen estimates that 20 or 30 or even more shots were fired. 
 
 Speaking to reporters after the assault, Florida Rep. Alan Grayson, a Democrat, said: "All the killing that was done was with an assault rifle, a single weapon...it was done very quickly also." 
 
 Investigators from the office of the medical examiner investigate on the west side of Pulse nightclub. (Photo: Doug Clifford, AP) 
 
 MULTI-HOUR HOSTAGE SITUATION ENSUES: 
 
 2 a.m. ET to 5 a.m. ET. Law enforcement and the shooter engage in three-hour standoff, with the assailant holding hostages. 
 
 Updates and pleas for help from frightened patrons, many hiding in a restroom, trapped in the club were zapped out to police, friends and the world via text messages and social media, such as Twitter. 
 
 The gunman, according to the FBI, made a call to 911 during the attack and pledged his support to the Islamic State, or ISIS. 
 
 Multiple emergency vehicles and law enforcement teams respond to the scene of the shooting. Bomb units were sent to the scene, as were hazardous material teams. 
 
 Around 3 a.m. Orlando Fire Department calls in the bomb squad. SWAT teams were also called in. 
 
 3:58 a.m. Orlando police, via Twitter, warn public to stay away from the nightclub area. 
 
 Shooting at Pulse Nightclub on S Orange. Multiple injuries. Stay away from area. pic.twitter.com/5Di2mc6XUY — Orlando Police (@OrlandoPolice) June 12, 2016 
 
 Law enforcement officials say there was "some communication" with assailant, but would not provide details. "Once the initial shots stopped we were dealing with a hostage situation," Mina said in a press conference. 
 
 Orlando Mayor Buddy Dyer says authorities learned through text messages from hostages in the club that between five and eight hostages were with the shooter in a room, while 15 to 25 others were in another room elsewhere in the nightclub. 
 
 SIEGE ENDS AS POLICE STORM CLUB, KILL ASSAILANT 
 
 5 a.m. About three hours after the standoff began, Orlando police chief John Mina says the decision was made to storm the club and "rescue patrons (hiding) in a bathroom" and others still trapped inside the club in an effort to minimize loss of life. The police, Mina said, used a BearCat armored rescue vehicle to "get through a club wall." 
 
 Cops also set off a "controlled detonation" around this time to distract the assailant. 
 
 After the BearCat rammed the club, the shooter opened the club's door, according to Mayor Dyer, and that's when cops took aim at the shooter. 
 
 Gunfire was "exchanged between the SWAT team and the suspect at 0500 hours," or 5 a.m., officials said later during a press conference. 
 
 Police said the gunman was killed in the firefight. 
 
 “We exchanged gunfire with the suspect, and he was dead at the scene," Mina said, adding that the SWAT team's decision to go in saved the lives of "at least 30 possible victims." 
 
 5:53 a.m. About an hour later the Orlando police department confirm via Twitter that the assailant, Mateen, had been killed: “Pulse Shooting: The shooter inside the club is dead.” 
 
 Pulse Shooting: The shooter inside the club is dead. — Orlando Police (@OrlandoPolice) June 12, 2016 
 
 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Melbourne vigil for Orlando victims | 1:43 Several hundred gather in Melbourne, Florida to honor the victims of the terror attack in Orlando. Video by Tim Shortt. Posted 6/17/16. 1 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Human Rights Campaign headquarters stages seven-story Orlando memorial | 0:53 The Human Rights Campaign transformed its Washington, D.C. Headquarters on Friday, June 17, with large-scale images of the 49 victims of the June 12 shooting at Pulse, a gay nightclub in Orlando, Florida. 2 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB "We're here to hold your heart." Counseling in Orlando crisis. | 1:57 Counselors helping those affected by the mass shooting in Orlando share insight into recognizing need, solutions and why they help. The First Unitarian Church of Orlando is among those hosting counseling. For more information call 407-822-5036. 3 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Remembering the 49 | 2:51 The names and faces of all 49 victims in the Orlando shooting. USA TODAY 4 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Obama offers condolences to Orlando victims | 1:09 President Barack Obama offered his condolences to those impacted by the deadly nightclub shooting in Orlando, Florida. Obama said that today the country is reminded of what is good and that there is compassion, empathy and decency. (June 16) AP 5 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Survivor: 'I was begging God please take me' | 1:51 A shooting victim describes how she made peace with dying as she saw bodies around her on the bathroom floor in the Orlando nightclub. (June 14) AP 6 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB FBI investigators interview Orlando gunman's wife | 0:38 The wife of the Orlando nightclub gunman is being interviewed by police and is cooperating with authorities. Noor Salman told police that her husband became radicalized in the last year. USA TODAY 7 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Orlando doctors: Mass shooting aftermath 'a war scene' | 1:39 Orlando first responders worked tirelessly caring for victims in Saturdays nightclub shooting. Hear how Orlando Regional Medical Center handled the pressure of what they described as something like a "war scene." 8 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Orlando shooting survivor: Shooter 'enjoyed' it | 0:25 Angel Colon is one of the survivors in the Orlando nightclub mass shooting. At a press conference alongside the medical team that saved him, he describes the shooter as enjoying himself while pulling the trigger. 9 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Buildings light up around the world for Orlando | 0:41 Famous buildings from around the world light up in rainbow colors to show support to Orlando shooting victims. USA TODAY 10 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB How the Pulse nightclub shooting unfolded | 1:31 A USA TODAY motion graphic detailing how America’s deadliest mass-shooting in history unfolded Sunday, June 12, 2016 in Orlando Florida. George Petras, Janet Loehrke, Ramon Padilla, Jim Sergent and Arek Sarkissian, USA TODAY Network. 11 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Preident Obama Slams Trump For Anti-Muslim Rhetoric | 2:36 President Obama spoke on Tuesday after meeting with his National Security Council. Bloomberg 12 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Omar Mateen: What we know about the Orlando shooter | 1:20 As more information continues to pour in about what happened at Pulse nightclub in Orlando, here's what we know about the shooter, Omar Mateen. VPC 13 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Hundreds gather in Orlando to honor shooting victims | 0:42 Hundreds of people gathered outside the Dr. Phillips Center for the Performing Arts in Orlando, Florida, to honor and remember those who lost their lives in the Orlando nightclub shooting. 14 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB U.S. cities show support for Orlando shooting victims | 0:53 From coast to coast, see how different U.S. cities are standing with Orlando after the deadliest mass shooting in U.S. history. 15 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Father of Omar Mateen: ‘What he did was completely act of terrorist’ | 1:14 Seddique Mateen, the father of Omar Mateen said he and his whole family were in shock at the actions of his son, who authorities say is responsible for killing dozens early Sunday at an Orlando nightclub. TCPalm.com 16 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB See how Clinton, Trump responded to the Orlando attack | 2:02 Hillary Clinton and Donald Trump made a statement about the Orlando nightclub shooting, suggesting ways to prevent a similar tragedy. 17 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Comfort dogs arrive in Orlando after nightclub attack | 1:04 Comfort dogs arrive in Orlando and are set straight to work meeting with community members affected by the gay nightclub shooting that left 49 people dead. Video provided by AFP Newslook 18 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Strength during tragedy, voices of hope | 2:16 One common thread from the people gathered at the mass shooting scene at an Orlando nightclub, was one of prayer and resilience. The voices of those who were at the scene helped to paint a picture of a community coming together after tragedy. USA TODAY 19 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Scenes from the mass shooting in Orlando | 1:50 Scenes from the mass shooting in Orlando. Andrew West/news-press.com 20 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Son sends text during shooting: 'I'm gonna die' | 1:16 Mina Justice's 30-year-old son Eddie texted her from the Pulse nightclub when the shooting occurred. He said he ran into a bathroom with other patrons to hide and told her to call police. He then texted her: "He's coming, I'm gonna die." AP 21 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Orlando gunman's ex-wife: He was mentally ill, abusive | 1:40 The ex-wife of the Orlando nightclub gunman says he was "mentally unstable and mentally ill." Sitora Yusifiy, speaking to reporters in Boulder, Colorado, says Omar Mateen was bipolar and also had a history with steroids. (June 12) AP 22 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Mourners come together at Lake Eola in Orlando | 0:57 Mitch Foster, organizer of the Lake Eola vigil, explains his motivation. David Oliver Wills sings a song in the twilight. USA TODAY 23 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB What we know about the Orlando nightclub shooting | 1:24 Scores of people were killed and many more were wounded in the shooting at a gay nightclub in Orlando, Florida. 24 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Five things to know about Omar Mateen | 0:42 Five things about Omar Mateen, the suspect in the deadly Orlando nightclub shooting which has now become the deadliest mass shooting in U.S. history. USA TODAY 25 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Again and again, Obama addresses the nation after a mass shooting | 4:34 President Obama's various responses to the mass shootings in the United States that have happened during his presidency. USA TODAY 26 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Deadliest mass shootings in the United States | 1:53 With at least 50 people dead, the mass shooting at an Orlando nightclub makes it the most deadly mass shooting in United States history. Here are the ten most deadly shootings in history. USA TODAY 27 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Officials speak out on the Orlando mass shooting | 1:40 Officials speak out on the Orlando mass shooting 28 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Politicians weigh in on deadliest shooting in U.S. | 1:11 President Obama, Hillary Clinton, Donald Trump and Florida Gov. Rick Scott addressed the deadly shooting at a gay nightclub in Orlando, Florida. 29 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Florida LGBT activist: We are resilient | 0:50 The first openly-gay elected official in Orlando responded to the mass shooting at a gay nightclub saying, 'if you think that you're going to stab at the heart of us by doing this horrible, violent act you're not because we love.' (June 12) AP 30 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Orlando Police Chief John Mina on why authorities waited three hours before attempting hostage rescue | 0:40 Orlando Police Chief John Mina on why authorities waited three hours before attempting hostage rescue. 31 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Bartender: My instinct was to get somewhere safe | 1:17 A bartender at a crowded gay nightclub in Orlando said her first instict was to get somewhere safe after a ginman opened fire, killing at least 50 people. (June 12) AP 32 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Fla. Senator: What is happening to our country? | 2:13 Florida Senator Bill Nelson said the shooting rampage at a crowded gay nightclub early Sunday in Orlando appears to be connected to 'Islamic radicalism.' (June 12) AP 33 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Obama: Orlando shooting was act of terror, hate | 5:28 President Obama delivered the remarks after a shooting at a gay nightclub in Orlando, Florida left more than 100 people dead and wounded. 34 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Florida Gov Rick Scott declares a state of emergency following Orlando mass shooting | 0:22 Florida Governor Rick Scott declares a state of emergency following Orlando mass shooting. 35 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB 50 killed in deadliest mass shooting in U.S. | 1:58 The Mayor of Orlando says there were 50 casualties and there are 53 more hospitalized after a mass shooting at a popular gay nightclub. (June 12) AP 36 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Doctor Describes 'Hectic' Scene at Fla. Hospital | 1:14 Medical staff at a Florida hospital say the situation is 'hectic' after a gunman opened fire at an Orlando nightclub early Sunday morning, leaving 50 dead and 53 injured. AP 37 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Gunfire erupts at Orlando nightclub | 0:38 A gunman wielding an assault-type rifle and a handgun took hostages and opened fire inside a popular, crowded Orlando, Florida nightclub. (June 12) AP 38 of 39 Skip in Skip x Embed x Share CLOSE DEADLY MASS SHOOTING AT ORLANDO NIGHTCLUB Raw: Video shows aftermath of nightclub massacre | 1:19 A gunman wielding an assault-type rifle and a handgun opened fire inside a crowded gay nightclub early Sunday, killing at least 50 people before dying in a gunfight with SWAT officers. It was the deadliest mass shooting in modern U.S. history. AP 39 of 39 Last VideoNext Video Melbourne vigil for Orlando victims 
 
 Human Rights Campaign headquarters stages seven-story Orlando memorial 
 
 "We're here to hold your heart." Counseling in Orlando crisis. 
 
 Remembering the 49 
 
 Obama offers condolences to Orlando victims 
 
 Survivor: 'I was begging God please take me' 
 
 FBI investigators interview Orlando gunman's wife 
 
 Orlando doctors: Mass shooting aftermath 'a war scene' 
 
 Orlando shooting survivor: Shooter 'enjoyed' it 
 
 Buildings light up around the world for Orlando 
 
 How the Pulse nightclub shooting unfolded 
 
 Preident Obama Slams Trump For Anti-Muslim Rhetoric 
 
 Omar Mateen: What we know about the Orlando shooter 
 
 Hundreds gather in Orlando to honor shooting victims 
 
 U.S. cities show support for Orlando shooting victims 
 
 Father of Omar Mateen: ‘What he did was completely act of terrorist’ 
 
 See how Clinton, Trump responded to the Orlando attack 
 
 Comfort dogs arrive in Orlando after nightclub attack 
 
 Strength during tragedy, voices of hope 
 
 Scenes from the mass shooting in Orlando 
 
 Son sends text during shooting: 'I'm gonna die' 
 
 Orlando gunman's ex-wife: He was mentally ill, abusive 
 
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 Five things to know about Omar Mateen 
 
 Again and again, Obama addresses the nation after a mass shooting 
 
 Deadliest mass shootings in the United States 
 
 Officials speak out on the Orlando mass shooting 
 
 Politicians weigh in on deadliest shooting in U.S. 
 
 Florida LGBT activist: We are resilient 
 
 Orlando Police Chief John Mina on why authorities waited three hours before attempting hostage rescue 
 
 Bartender: My instinct was to get somewhere safe 
 
 Fla. Senator: What is happening to our country? 
 
 Obama: Orlando shooting was act of terror, hate 
 
 Florida Gov Rick Scott declares a state of emergency following Orlando mass shooting 
 
 50 killed in deadliest mass shooting in U.S. 
 
 Doctor Describes 'Hectic' Scene at Fla. Hospital 
 
 Gunfire erupts at Orlando nightclub 
 
 Raw: Video shows aftermath of nightclub massacre 
 
 Read or Share this story: http://usat.ly/28v6WZe ||||| Media playback is unsupported on your device Media caption Seddique Mateen said he did not understand why his son had carried out the shooting 
 
 The father of a gunman who killed dozens of people in an Orlando gay club says he did not know that his son had a "grudge in his heart". 
 
 Omar Mateen killed 49 people and wounded 53 more in the deadliest mass shooting in recent US history, before being shot dead by police. 
 
 Seddique Mateen said he did not understand why his son had carried out the shooting at the Pulse nightclub. 
 
 The so-called Islamic State group (IS) called Omar Mateen one of its soldiers. 
 
 In a statement posted online and addressed to people in his native Afghanistan, Seddique Mateen said his son had been "a very good boy", who had a wife and a child. 
 
 "I don't know what caused it," he said. "I never figured out that he had a grudge in his heart... I am grief-stricken." 
 
 Live updates 
 
 How attacks unfolded 
 
 Who was Omar Mateen? 
 
 Orlando shooting: Special report 
 
 He added he did not know why his son had committed such an act during the Islamic holy month of Ramadan, adding that the fate of gay people was "not in the hands of humans" as it was, he said, only God who could judge. 
 
 IS had called for attacks on the West during Ramadan. 
 
 On Sunday, Seddique Mateen said: "We are apologising for the whole incident. We are in shock, like the whole country." 
 
 He said his son had been angered after seeing two men kissing in Miami. 
 
 What happened on the night? 
 
 The attack began at about 02:00 local time (06:00 GMT) on Sunday. There was an exchange of fire with a police officer working at the club, after which the suspect took hostages. 
 
 At 05:00 a police assault team went into the club after police received text messages and phone calls from some of the hostages. Mateen was killed in an exchange of fire. 
 
 States of emergency have been declared in the city of Orlando and surrounding Orange County. 
 
 Media playback is unsupported on your device Media caption President Obama: "We are united in grief, outrage - and resolve" 
 
 Who were the victims? 
 
 Image copyright Reuters Image caption Clockwise from top left: Orlando shooting victims Edward Sotomayor, Stanley Almodovar, Luis Omar Ocasio-Ocampo, Juan Ramon Guerrero, Luis Vielma and Eric Ivan Ortiz-Rivera 
 
 So far, 24 victims have been named: 20 men and four women. They include: 
 
 Edward Sotomayor , 34, who worked for a company that organised gay cruises 
 
 , 34, who worked for a company that organised gay cruises Stanley Almodovar , 23, a pharmacy technician who was remembered as "kind and sassy" 
 
 , 23, a pharmacy technician who was remembered as "kind and sassy" Kimberly Morris , 37, who had only recently moved to Orlando and worked at Pulse as a bouncer 
 
 , 37, who had only recently moved to Orlando and worked at Pulse as a bouncer Luis Vielma , 22, who worked at the Harry Potter section at Universal Studios - author J K Rowling paid tribute to him online 
 
 , 22, who worked at the Harry Potter section at Universal Studios - author J K Rowling paid tribute to him online Eddie Justice, 30, who sent his mother a series of text messages while inside the club - read more on him here 
 
 Read more on the victims here 
 
 LGBT community under siege 
 
 Who was the killer? 
 
 Image copyright CBS News Image caption US media have published pictures of the suspect, Omar Mateen 
 
 Mateen, a US citizen of Afghan descent who was born in New York and lived in Florida, was not on a terrorism watch list. 
 
 However, the FBI interviewed him twice in 2013-14 after he made "inflammatory remarks" to a colleague, before closing its investigation. 
 
 Mateen had legally purchased several guns in the days before the attack. 
 
 A statement on the IS-affiliated Amaq news agency said an IS "fighter" was responsible and on Monday, the group's al-Bayan radio called Mateen "one of the Caliphate's soldiers in the US". 
 
 An FBI spokesman said Mateen had called the emergency services before the attack and sworn allegiance to IS. 
 
 The AR-15 semi-automatic rifle One of the two guns used by Omar Mateen 3.3 million AR-15s in the US in 2012 (estimated) 45 rounds per minute 
 
 26 people killed by AR-15 in Sandy Hook in 2012 
 
 0 days' wait needed to obtain one in Florida Getty Images 
 
 Image copyright Omar Mateen Image caption Mateen's father said his motives had nothing to do with religion 
 
 On Sunday, Mateen's father said religion had had nothing to do with the attack. 
 
 A security company that Mateen used to work for said he had been vetted twice. 
 
 The checks in 2007 and 2013 did not reveal anything of concern, G4S said, and Mateen had carried a gun as part of his job. 
 
 Read more on Omar Mateen 
 
 Analysis: Gordon Corera, BBC Security Correspondent 
 
 The FBI's admission that it investigated Mateen on a number of occasions will raise questions not just for law enforcement but for the wider US security community. 
 
 It has frequently been the case in a number of countries that individuals are assessed as not dangerous at one point and then turn out to be a threat later. In the UK, this led the Security Service to place more emphasis on going back and checking up on previous cases to ensure that the threat assessment made in the past had not changed. 
 
 Keeping detailed files and watch on people can be resource-intensive, however, and has raised concerns over civil liberties in the past. 
 
 As the concern over home-grown terrorism in the US grows, there may be pressure to do more and there may also be further questions as to whether a previous investigation for possible terrorism should place people not just on No-Fly lists, but also restrict their ability to purchase weapons. 
 
 Ex-wife: Mateen was 'disturbed' 
 
 Media playback is unsupported on your device Media caption Sitora Yusufiy, supported by her fiance, talks about her ex-husband, Omar Mateen 
 
 Sitora Yusufiy lived with Mateen for four months in 2009. She said her family had "rescued" her from the relationship when they became aware he was being physically abusive. 
 
 He beat her up regularly during their short-lived marriage for trivial things like not doing laundry, she said. 
 
 "When he would get in his tempers, he would express hate toward everything. He was mentally unstable and mentally ill: that's the only explanation that I could give." 
 
 Image copyright EPA Image caption Vigils were held in US cities, including here in San Francisco, to mourn the victims of the Orlando shooting 
 
 Image copyright AP Image caption A DJ who was in the club at the time of the attack was comforted by a friend 
 
 Media playback is unsupported on your device Media caption Nihad Awad: "Homophobia, transphobia, Islamophobia are interconnected systems" 
 
 The death toll means that the Orlando attack surpasses the 2007 massacre at Virginia Tech, which left 32 people dead. 
 
 According to the crowd-sourced Mass Shooting Tracker, the US suffered 372 mass shootings last year, defined as a single incident that kills or injures four or more people. Some 475 people were killed and 1,870 wounded. 
 
 The latest incident came as Orlando was still reeling from the fatal shooting on Friday night of 22-year-old singer Christina Grimmie following a concert in the city. ||||| Get daily news updates directly to your inbox Subscribe Thank you for subscribing We have more newsletters Show me See our privacy notice Could not subscribe, try again later Invalid Email 
 
 Horrifying footage has emerged from the tragic shooting at Pulse nightclub in Orlando on Sunday morning. 
 
 Amanda Alvear posted a video of her night out at Pulse to her Snapchat exclusively obtained by the Mirror through a friend. 
 
 Clips initially show her having fun with friends, but later on the sound of gunfire rings out loudly. 
 
 It is the first footage from inside the nightclub massacre, with Amanda having since been confirmed as one of the fatalities. 
 
 Ashley Velez, sister of the 25-year-old Puerto Rican, pid tribute to Amanda, saying: "I love you baby girl. 
 
 Keep up to date with the latest from Orlando on our live blog here 
 
 (Image: Facebook) 
 
 "You were and will always be my baby sister. I'm so heartbroken. 
 
 "You could make anyone's day with the smile of yours." 
 
 Mercedez Marisol Flores, who was at Pulse with her best friend Amanda, has also been named among the victims. 
 
 (Image: PA) 
 
 The 26-year-old worked at the retailer Target and lived in the Florida city of Davenport. 
 
 Read more: 
 
 Josean Garcia said: "She was the one I fought with the most ... but somehow we understood each other. We did everything together." 
 
 (Image: Getty Images) 
 
 Omar Mateen, 29, was identified as the shooter by his ex-wife. 
 
 Read more: 
 
 He was later gunned down by a SWAT team who are believed to have used explosives to distract Mateen after he took hostages. 
 
 (Image: Barcroft) 
 
 ISIS has since claimed responsibility for the shooting. 
 
 (Image: Reuters) 
 
 Read more: 
 
 “The armed attack that targeted a gay night club in the city of Orlando in the American state of Florida which left over 100 people dead or injured was carried out by an Islamic State fighter,” Amaq News Agency reported. 
 
 Islamic State then reiterated once more a claim of responsibility for the attack today. 
 
 "One of the Caliphate's soldiers in America carried out a security invasion where he was able to enter a crusader gathering at a nightclub for homosexuals in Orlando, Florida ... where he killed and injured more than a hundred of them before he was killed," the group said in a broadcast on its Albayan Radio. 
 
 (Image: Reuters) 
 
 Although the group claimed responsibility, this did not necessarily mean it directed the attack: there was nothing in the claim indicating coordination between the gunman and ISIS before the rampage. 
 
 (Image: Getty) 
 
 Democratic candidate Hillary Clinton and her Republican rival Donald Trump are both expected to address the issue later today at campaign events. 
 
 (Image: Getty) 
 
 Some 350 patrons were attending a Latin music event at Pulse, a well-known gay nightspot in the city, and survivors described scenes of carnage and pandemonium as the shooter took hostages inside a bathroom. 
 
 Partygoer Eddie Justice texted his mother Mina from the toilets inside the club as she waited outside. 
 
 He wrote: “He’s coming. I’m gonna die,” before then saying: “He has us, and he’s in here with us.” 
 
 It was the last she heard from him and he was later confirmed as one of the victims. 
 
 (Image: Facebook) 
 
 Another reveller, Kenneth Melendez, said four of his friends were shot and taken to hospital. 
 
 He said: "At first, when I heard the shots I thought it was part of the music, but then we realised it was really happening. 
 
 "I started running and saw someone bleeding from the arm and I was like, wow, this is really happening and I kept running." 
 
 (Image: Twitter / MEN Media) 
 
 Witness Juan Rivera added: “Around 2am when the club was about to close we heard shooting outside – once they finished the shooter came inside and he had a rifle and he started shooting everywhere. We heard about 30 shots and all of a sudden the lights went off and we had blood all over our shirts.” 
 
 Mr Rivera said the gunman, who was thought to be wearing a suicide vest, said nothing and was firing as he blocked one of the two exits from the club.
– A mother whose son was killed in the Orlando, Fla., shooting has shared the terrifying final text messages she received. Mina Justice, who spoke to the AP before her 30-year-old son, Eddie, was confirmed dead, says she was woken up at 2:06am by the messages: "Mommy I love you" and "In club they shooting." He told her he was trapped in the bathroom of the Pulse nightclub and urged her to call police. She called 911 and exchanged more messages with her son as she spoke to the dispatcher. "He's coming. I'm gonna die," Eddie texted at 2:39am. "Hurry," he wrote minutes later. "He's in the bathroom with us." She asked him, "Is the man in the bathroom wit u?" At 2:50am, he wrote "He's a terror," and then sent his final message: "Yes." It would be more than two hours until police stormed the club, killing gunman Omar Mateen after the deadliest mass shooting in US history. Eddie Justice was on a partial list of victims released by police Sunday night, the Guardian reports. His mother says he was an accountant who was generally a homebody but who loved to make people laugh. The Orlando Sentinel has the names and stories of more of the 50 victims, almost all of whom were in their 20s or 30s. (On Sunday night, vigils were held across the US.)