Image caption The Free Syrian Army and other rebel fighters have been engaged in fierce fighting in Aleppo 
 
 US Defence Secretary Leon Panetta says Syrian President Bashar al-Assad's assault on the city of Aleppo will be "a nail in his coffin". 
 
 Mr Panetta was speaking at the start of a five-day Middle East tour. 
 
 Heavy fighting is continuing in Syria's largest city where government forces are trying to oust rebel fighters. 
 
 UN humanitarian chief Valerie Amos said 200,000 people had fled the fighting in Aleppo and that an unknown number were trapped. 
 
 She said that the city urgently needed supplies including food and water. 
 
 Mr Panetta said the Syrian crisis was deepening and that President Assad was hastening his own demise. 
 
 "If they continue this kind of tragic attack on their own people... I think it ultimately will be a nail in Assad's coffin," he told reporters. 
 
 "What Assad has been doing to his own people and what he continues to do to his own people makes clear that his regime is coming to an end. It's lost all legitimacy." 
 
 He added: "It's no longer a question of whether he's coming to an end, it's when." 
 
 At the scene A hole-in-the-wall bakery had just reopened its doors after being closed for more than a day. Most food shops in the turbulent districts are now closed. Rebel fighters tried to marshal the crowds as hundreds of hungry and increasingly desperate residents clamoured for the thin round loaves. Suriya had finally reached the front of the queue and the middle-aged mother thrust her hand through the railings outside the bakery, grasping for the bread. Like many poor Syrians she has a large family to feed and with no fresh fruit or vegetables available this is her only chance to get food. "A lot of poor people are suffering from a lack of food and water," she complained. "Many are going to bed hungry." Their suffering does not seem likely to end soon. Food, water and power shortages have made life hard for residents. The ever-present danger from bombs and bullets is making it intolerable. Fear and hunger in Aleppo 
 
 Mr Panetta's tour will include talks in Tunisia, Egypt, Israel and Jordan. 
 
 He said he aimed to reinforce an international consensus that Mr Assad must step down and allow a peaceful transition to democracy. 
 
 The defence secretary said he would also continue efforts to ensure that Syria's stockpiles of chemical weapons did not fall into the wrong hands. 
 
 Baroness Amos, speaking in New York, said that the Red Cross and the Syrian Arab Red Crescent estimated that 200,000 people have fled Aleppo and surrounding areas in the past two days. 
 
 "It is not known how many people remain trapped in places where fighting continues today," she said. 
 
 "I call on all parties to the fighting to ensure that they do not target civilians and that they allow humanitarian organisations safe access." 
 
 UK-based activist group the Syrian Observatory for Human Rights described the situation in Aleppo as "a full-scale street war". 
 
 The BBC's Ian Pannell, who was in Aleppo on Saturday, said government troops were trying to push into rebel-held neighbourhoods and there was fierce fighting. 
 
 Civilians are facing power cuts and food shortages, he says. 
 
 Late on Sunday, Syrian troops said they had recaptured the south-west district of Salah al-Din from the rebels. 
 
 "Complete control of Salah al-Din has been (won back) from those mercenary gunmen," a military officer told Syrian state TV. 
 
 "In a few days safety and security will return to the city of Aleppo." 
 
 Despite the army's statement, activists said fighting was continuing in Salah al-Din on Sunday night. 
 
 Aleppo activist Abo Aref al-Halabi told the BBC's Newsday programme on Monday that it had been a "terrible night" in the city. 
 
 "Nobody can sleep. Everywhere you can hear [the sound of] bombs," he said. 
 
 "The Assad armies are using mortars, they are using tanks, bombs, they are using helicopters, missiles coming from helicopters, to the Salah al-Din area." 
 
 He said some buildings were on fire and others had collapsed. 
 
 Battle-hardened 
 
 Our correspondent says that although the rebels are outgunned, they are fighting an effective guerrilla war in the streets of the city. 
 
 Many are more battle-hardened than their adversaries and they are making their own improvised explosive devices, he adds. 
 
 Syrian Foreign Minister Walid Moualem, on a visit to Iran, said that the government was winning its war against the rebels. 
 
 "Today I tell you, Syria is stronger," he said. 
 
 "In less than a week they were defeated (in Damascus) and the battle failed. So they moved on to Aleppo and I assure you, their plots will fail." ||||| ALEPPO, Syria (Reuters) - Syrian troops said they had recaptured a district of Syria's largest city Aleppo, after heavy fighting against rebels who remain in control of swathes of the commercial hub despite being pushed out of the capital Damascus. 
 
 The past two weeks have seen forces of President Bashar al-Assad struggle as never before to maintain their grip on the country after a major rebel advance into the two main cities and a July 18 explosion that killed four top security officials. 
 
 Government forces have succeeded in imposing their grip on Damascus but rebel fighters gained control of parts of Aleppo, a city of 2.5 million people, where Reuters journalists have toured neighborhoods dotted with Free Syrian Army checkpoints flying black and white Islamist banners. 
 
 U.S. Defense Secretary Leon Panetta said attacks on Aleppo were putting the nail in the coffin of Assad's government, showing he lacks the legitimacy to rule. 
 
 "If they continue this kind of tragic attack on their own people in Aleppo, I think it ultimately will be a nail in Assad's own coffin," Panetta said, speaking to reporters at the start of a weeklong trip to the Middle East and North Africa. 
 
 "What Assad has been doing to his own people and what he continues to do to his own people makes clear that his regime is coming to an end. It's lost all legitimacy," he said, adding, "It's no longer a question of whether he's coming to an end, it's when. 
 
 Fighting for the past several days has focused on the Salaheddine district in the southwest of Aleppo, where government troops have been backed by helicopter gunships. 
 
 Rebel fighters, patrolling opposition districts in flat-bed trucks flying green-white-and-black "independence" flags, said they were holding off Assad's forces in Salaheddine. However, the government said it had pushed them out. 
 
 "Complete control of Salaheddine has been (won back) from those mercenary gunmen," an unidentified military officer told Syrian state television late on Sunday. "In a few days safety and security will return to the city of Aleppo." 
 
 Reuters journalists in the city were not able to approach the district after nightfall on Sunday to verify whether rebels had been pushed out. The pro-opposition Syrian Observatory for Human rights said fighting was continuing there. 
 
 The government also declared victory on Sunday in the battle for the capital, which the rebels assaulted in force two weeks ago but have been repulsed in unprecedented fighting. 
 
 "Today I tell you, Syria is stronger ... In less than a week they were defeated (in Damascus) and the battle failed," Foreign Minister Walid Moualem said on a visit to Iran, Assad's main ally in the region. 
 
 "So they moved on to Aleppo and I assure you, their plots will fail." 
 
 Rebel-held areas of Aleppo visited by Reuters were almost empty. Fighters were basing themselves in houses. 
 
 Cars entering one Aleppo district came under fire from snipers and a Reuters photographer saw three bodies lying in the street. Unable to move them to hospital for fear of shelling, residents had placed frozen water bottles on two of the corpses to slow their decomposition in the baking heat. 
 
 A burnt out tank lay in the street, while nearby another one had been captured intact and covered in tarpaulin. Burnt cars could be seen in many streets, some marked with "shabbiha" - a reference to pro-Assad militiamen. 
 
 Near the centre of town, most shops were shuttered, some with "Strike" painted over them. The only shop doing business was a bakery selling subsidized bread, where the queue stretched around the block. 
 
 U.N. Undersecretary-General for Humanitarian Affairs Valerie Amos said 200,000 people had fled the fighting in and around Aleppo in the last two days, and the violence across Syria made it hard for humanitarian agencies to reach them. 
 
 "Many people have sought temporary shelter in schools and other public buildings in safer areas. They urgently need food, mattresses and blankets, hygiene supplies and drinking water." 
 
 Assad's ruling structure draws strongly on his Alawite minority sect, an offshoot of Shi'ite Islam, while his opposition is drawn largely from the Sunni Muslim majority, backed by Sunni leaders who rule nearly all other Arab states. 
 
 That has raised fears the 16-month conflict could spread across the Middle East, where a sectarian divide between Sunnis and Shi'ites has been at the root of violence in Iraq, Lebanon, Bahrain and elsewhere. 
 
 Shi'ite Iran demonstrated its firm support for Assad by hosting his foreign minister. At a joint news conference with Moualem, Iran's Foreign Minister Ali Akbar Salehi rebuked the West and Arab states for holding the "illusion" that Assad could be easily be replaced in a managed transition. 
 
 CRUCIAL TEST 
 
 In Damascus, many residents have fled fighting in the outskirts for relative safety in the heart of the capital. 
 
 In the centre, shops open only between 9 a.m. and 3 p.m., food prices have soared and no one dares walk outside after dusk, even in the holy month of Ramadan when streets are normally packed late into the night with people breaking the fast. 
 
 "To begin with I was with the regime, for sure," said Ahmed, from one of the southern suburbs where the army, backed by helicopters and tanks, launched its counter-offensive. 
 
 "But now, no, the regime must go. Take what they want with them, but they must go." 
 
 The battle for Aleppo is a decisive test of the government's ability to put down the revolt after the July 18 explosion killed four of its top security officials and wrecked the Assad family's image of untouchable might. 
 
 It has committed huge military resources to Aleppo after losing control of outlying rural areas and some border crossings with Turkey and Iraq. 
 
 (Additional reporting by Yara Bayoumy and Dominic Evans in Beirut, Yeganeh Torbati in Dubai and a reporter in Damascus who cannot be identified for security reasons; Writing by Peter Graff; Editing by Sophie Hares) ||||| 4.22pm BST 
 
 • The Syrian chargé d’affaires in London has resigned saying he is no longer willing to represent a "violent and oppressive" regime. Khaled al-Ayoubi was the most senior Syrian diplomat serving in London. His departure was announced by the UK Foreign Office, which described it as "another blow to the Assad regime". It urged others to follow his example. 
 
 • Rebel fighters claim to have captured the Hryatan military base and Anadan checkpoint, north-west of Aleppo. Video showed them celebrating on captured tanks and removing supplies. Colonel Abdel Naser, the commander in charge of the battle told the Guardian's Luke Harding that his troops seized eight tanks and 10 armoured vehicles, as well as mortars and lots of weapons. He said one rebel fighter was killed. The rebels now control a strategic land corridor in northern Syria from Turkey all the way to Aleppo's outskirts. 
 
 • Opposition activists have denied government claims that troops loyal to Bashar al-Assad have "purged" the neighbourhood of Salaheddin, in Aleppo. Salaheddin has been a rebel stronghold since the battle began 10 days ago and the scene of intense clashes in recent days. One activist told the Guardian that there had been heavy bombardment of the area overnight but Free Syrian Army troops remained, in defensive positions. Abu Obeida also said that 90% of residents had fled the area because of the fighting. 
 
 • A Syrian brigadier general who was deputy chief of police in Syria's Latakia region, has defected to Turkey. The official says the general was among a group of 12 Syrian officers who crossed into Turkey late Sunday. The brigadier general's defection raises the number of generals to have defected and crossed into Turkey since the start of the 17-month-old uprising to 28, according to AP. Latakia is the de facto capital of the Alawite heartland on the Mediterranean coast, 
 
 • The US defence secretary, Leon Panetta, criticised the Syrian army's use of heavy weapons in putting down the rebellion, describing it as "a nail in Assad's coffin". Beginning a tour of the Middle East, he said: 
 
 If they continue this kind of tragic attack on their own people ... I think it ultimately will be a nail in Assad's coffin. 
 
 • France, which is to assume the UN security council's rotating presidency in August, is to call an emergency ministerial meeting on Syria. Foreign minister Laurent Fabius said the aim of the meeting would be "to try to stop the massacres and to prepare a political transition". 
 
 • Reports suggest that jihadists are playing a bigger role in the uprising against the Assad regime. Al-Jazeera said: "Some groups say they are affiliated with al-Qaida, fly its flags, and say they now have training camps inside the country." The New York Times reported: "Even less-zealous resistance groups are adopting a pronounced Islamic aura because it attracts more financing." The Free Syrian Army has acknowledged the presence of jihadists in the country, while distancing itself from them. The opposition insists they are few and far between. ||||| Mr. Assad’s recent military successes have depended heavily on help from Russia, Iran and the Iranian-backed Lebanese Shiite militant group Hezbollah, which are reviled by many of Mr. Assad’s Sunni opponents, and viewed with unease even by some of his supporters because of their growing power in the country. Large areas of Aleppo and other cities and towns have been reduced to rubble by the fighting. And rebel forces, Kurdish militias and Islamic State fighters are still operating in large areas of northern and eastern Syria. 
 
 That has been vividly clear in recent days, with Islamic State fighters advancing in the desert city of Palmyra, amid its ancient ruins, as the government focused on Aleppo. 
 
 For civilians trapped behind the battle lines in Aleppo, though, more urgent questions loomed. Time appeared to be running out to strike a deal to allow them to evacuate. 
 
 Rebel and opposition leaders want evacuees to be given an option to go to territory they control. Many of the remaining civilians refuse to go to government-held territory because they are afraid they would be jailed and tortured there. Others say the bombardment in their districts is too intense to allow any escape. There were also reports in state news media of rebel shelling of government-held areas. 
 
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 According to the Russian government, Mr. Assad’s main foreign backer, more than 100,000 people have fled from the rebel enclave to government-held areas, and 2,200 rebel fighters have surrendered. At least 13,000 people have fled in the past 24 hours, it said. 
 
 But there are still believed to be thousands of civilians trapped in districts that have been bombarded for more than 24 hours, while the army and its militia allies seized most of the southern part of the city. 
 
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 “An important call in the name of civilians to help them,” Abdelkafi al-Hamdo, a teacher and antigovernment activist, said in a text message to a group of journalists. “Stop bombing. Take them out.” 
 
 The situation was so desperate, residents said, that it was unclear whether rebels and civilians there could even hold a meeting to decide whether to surrender and evacuate. 
 
 “Believe me, no one rejects the safety evacuation,” one resident, Yasser Abu al-Joud, said in a text message to the journalists’ group. “All of us are waiting, dying now in the last neighborhoods.” 
 
 Hisham al-Skeif is a civilian member of the local council that had tried to govern the rebel-held areas of Aleppo, which once included half the city. Mr. Skeif expressed frustration that while international officials were in contact with rebel leaders, no one appeared to be talking directly to the trapped civilians. 
 
 “All the political activists and the media, the relief workers, the unarmed, we are about 1,000, including our families,” he said. Though the government has said it would offer amnesty to anyone who surrenders, “if the regime entered, we will be slaughtered,” he said. “Of course everybody is negotiating with those who are armed, but we are not armed.” 
 
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 “The armed can defend themselves, but we can’t,” he added. 
 
 Mr. Hamdo said in a series of text messages that families in Aleppo were “waiting death together.” 
 
 “People are running, don’t know where,” he wrote. “People are under the rubble alive, and no one can save them. Some people are injured in the streets, and no one can go to help them cuz the bombs are always on the same place.” 
 
 Some rebel leaders have said that the United States, which backs some rebel groups, sent them a proposal that would allow evacuees their choice of destination, under security guarantees from Russia. But trust has eroded, and no agreement had emerged by Monday night. 
 
 Syrian and Russian officials say the offensive in Aleppo will continue until rebels surrender or die. 
 
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 “The issue of withdrawing militants is the subject of separate agreements,” Sergei Ryabkov, the Russian deputy foreign minister, told the Ria news agency on Monday. “This agreement has not yet been reached, largely because the United States insists on unacceptable terms.” 
 
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 The sticking point for months has been a dispute between Russia and the United States over what to do about fighters linked with Al Qaeda who are among the rebel groups in eastern Aleppo. The United Nations estimates that about 10 percent of the 8,000 rebel fighters in the city belong to a Qaeda-linked group, the Levant Conquest Front. The rebels and their international backers say the figure is much lower; the government says it is much higher. 
 
 Before the government broke through the rebel defenses, the United Nations was proposing that the Levant Conquest Front leave Aleppo in exchange for three main broad concessions from the government side: an end to bombardment; protection and aid for remaining civilians; and some form of local administration for rebel areas. 
 
 But the government rejected any form of self-government, saying that it would “reward terrorists,” while the rebels rejected versions of the deal that did not include it. Now, there is no meaningful rebel territory left for the local opposition council to govern. 
 
 “We are hearing terrifying S O S calls from the civilians, but we can’t do anything,” said Bassem al-Hajj, a spokesman for Nour al-Din al-Zenki, one of the main rebel groups in Aleppo. “The fighters are defending, but they are retreating under pressure. Unfortunately, the situation is very bad.” 
 
 The focus has now shifted to ending the bombardment and protecting the remaining civilians from reprisals, a reasonable fear in a country where, throughout the six-year conflict, people have been tortured and killed in prison for opposing the government. 
 
 “Understand this,” Mr. Hamdo, who said his wife and small daughter were cowering in their apartment with him, wrote on Twitter. “I can’t simply surrender and being captive. I am speaking out, and this is a crime. I might then ask death, and not got it.” 
 
 Malek, an activist who asked to be identified only by his first name for fear that he would soon find himself in government territory, said he had moved on Monday to a safer place for the 10th time since the offensive began, along with his cats, Rocky and Loz, the Arabic word for almond. 
 
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 “Why should I lie? I’m not well,” he said in a series of voice messages. “We are people, are being deleted from the human map. We have two neighborhoods and one street, and the regime will keep bombing this small area.” 
 
 Bodies were stuck under the rubble, Malek said, and even members of the White Helmets civil defense group could not rescue anyone, because the group’s equipment had been destroyed and their members scattered by the shelling. 
 
 Still attempting to find humor, he said that his cat Rocky had lost “his fiancée” along the way. “Now he’s lonely,” Malek said. 
 
 Dr. Salem, a dentist who had kept his clinic open until last week, finally moved to one of the last rebel neighborhoods as his own was taken by government forces. He said he walked through streets shrouded in smoke, and littered with the dead and wounded, to a small area where thousands were crowded in a shrinking space. “There will be a massacre if one rocket falls here,” said Dr. Salem, using only his first name.
– As brutal fighting continued for control of Syria's largest city, a furious Leon Panetta vowed that the regime's assault on Aleppo would be a "nail in the coffin" of Syrian President Bashar al-Assad. Some 200,000 residents have fled the besieged city as rebels battle to hold off government troops, reports the BBC. Several were huddling in schools and other public buildings in a bid to escape the violence, reports CNN. Many are fleeing to other towns, or over the Turkish border; Jordan has also opened an emergency refugee camp to house Syrians fleeing violence. The Syrian regime claimed late yesterday to have taken control of a district of the city of 2.5 million, but Reuters reports several communities in Aleppo were still dotted with rebel checkpoints. If the government troops "continue this kind of tragic attack on their own people in Aleppo, I think it ultimately will be a nail in Assad's own coffin," Panetta told reporters at the start of the defense secretary's week-long trip to the Middle East and North Africa. "What Assad continues to do to his own people makes clear that his regime is coming to an end. It's lost all legitimacy. It's no longer a question of whether he's coming to an end, it's when."