Media playback is unsupported on your device Media caption The BBC's Wyre Davies says government forces have launched a co-ordinated attack on Aleppo 
 
 Fighter jets have bombed eastern areas of Syria's second city Aleppo, a BBC reporter near the city says. 
 
 The attack, which followed an artillery barrage, is seen as a significant escalation in the conflict. 
 
 Rebels launched an offensive against Aleppo at the weekend in an attempt to wrest the city from government forces. 
 
 US Secretary of State Hillary Clinton says territorial gains made by the rebels will eventually result in a "safe haven" inside Syria. 
 
 "We have to work closely with the opposition, because more and more territory is being taken," she told reporters in Washington. That would become a safe haven which would provide a base for further action by the opposition, she said. 
 
 At the scene The military's response today marked a sharp escalation in this battle. Helicopter gunships spun through the skies throughout the day. Sustained artillery and mortar rounds pounded restive neighbourhoods. But it was what happened late in the afternoon that underlined the grave risk to the government of losing ground in what is Syria's largest city and its economic capital. First came an unmistakeable sound that has so far been absent in this conflict - the roar of fighter jets. What appeared to be Russian-made MiG planes arced through the sky. We watched as they dropped in, bombing and strafing rebel positions. Dead and wounded civilians and fighters were taken to hospitals and makeshift clinics as the human cost of this conflict continues to grow. Warplanes hit Aleppo 
 
 Mrs Clinton said the pace of events was accelerating inside Syria and called on the opposition to be prepared for a transition of power, adding that it was not yet too late for President Assad himself to prepare for such a handover. 
 
 In one of the deadliest incidents of the day, opposition activists reported that at least 20 worshippers were killed as they went into a mosque in a village close to the city of Hama. 
 
 Troops and militia loyal to President Assad left a roadblock and opened fire on the men who were arriving for evening prayers in Shariaa, one activist told Reuters news agency. 
 
 Foreign journalists work under intense restrictions in Syria so reports by both sides are hard to verify. 
 
 Police besieged 
 
 Earlier in Aleppo, government forces launched what correspondents described as a co-ordinated attack on the Tariq al-Bab area in the east of the city late on Tuesday afternoon, first with a 10-minute barrage of 30 shells and then with bombing runs from fixed-wing jets. 
 
 It was thought to be the first time that Syrian fighter planes had been used for bombing urban targets during the conflict, as the government attempted to take back districts of Syria's commercial centre seized by the rebels. 
 
 There are reports of dozens of casualties and widespread damage. The BBC's Ian Pannell, on the outskirts of Aleppo, says civilians and fighters are among the dead and wounded. 
 
 Helicopter gunships have been involved in the clashes in the city throughout the day, he says. 
 
 Fierce fighting has been reported close to the historic Old City. A French correspondent there has spoken of rebels besieging a police headquarters close to the walls of the Old City, which is a world heritage site. 
 
 Government forces have already regained control of most areas of Damascus that were captured by rebels last week. Opposition activists report renewed raids by troops in the Tadamon, Qadam and Assali areas of the city. 
 
 State television has broadcast video of soldiers apparently securing and checking heavily shelled suburbs in the south of the capital. 
 
 The battle for Aleppo, Syria's most populous city, appears to have spread to much of the city, with rebels claiming control of several areas. 
 
 State forces appear to have focused their counter-attack on the Sakhour area to the east of the city centre, where rebels destroyed several tanks on Monday, the BBC's Jim Muir reports from neighbouring Lebanon. 
 
 'Border shelling' 
 
 The violence on Tuesday claimed the lives of more than 100 people in Syria, according to the opposition Local Co-ordination Committees, including 20 in Aleppo. 
 
 Image caption The shell of a burnt-out bus is seen in the Qabun district of Damascus. In pictures: Syria conflict 
 
 Thirteen people died in a revolt in Aleppo prison, activists said, when security forces reportedly opened fire and used tear gas on detainees. 
 
 Explosions and fires have also been reported from the jail in Homs where a similar mutiny took place. 
 
 Unverified reports said hundreds of refugees had become caught up in violence while trying to flee the country across its eastern border with Iraq. 
 
 Three people were wounded when Syrian forces shelled the Syrian side of the Boukamal crossing on the Euphrates river, where a crowd of Iraqis and Syrians were waiting to leave, a source has told the BBC. 
 
 The deteriorating security situation has prompted 10,000 Iraqi refugees to leave Syria in less than a week, according to the UN refugee agency. 
 
 Elsewhere, 10 people were reported killed when a shell hit their car near Hama and a family was said to have died during a bombardment of Deraa in southern Syria. 
 
 Chemical threat 
 
 As the battle for control of Syria's biggest cities spreads, international concern about Syria's chemical weapons stockpile has spread to its ally, Russia. 
 
 The US and the UN have already issued a warning to Damascus, after a Syrian spokesman said its weapons would never be used internally but could be deployed against "external aggression". 
 
 Russia's foreign ministry said on Tuesday that it "proceeds from the assumption that the Syrian authorities will continue to rigorously abide by their international obligations". 
 
 In other developments ||||| ALEPPO, Syria — On a city street where shops once stayed open late selling computers and electronics, children in flip-flops and dusty clothes clambered over the charred, twisted mass of a tank. The hatch hung open and a few kids peered inside, the soldiers' bodies now gone. 
 
 The destroyed army tank, once a rarity in the uprising against President Bashar Assad, symbolizes a shift in the balance of the 17-month conflict in Syria, one that augurs gains for the rebels, but also raises the prospect of an increasingly bloody arms race. 
 
 For months, rebels with their Kalashnikov assault rifles and homemade explosives were little match for the government's armored vehicles, and often fled after putting up a weak fight. But now, armed with new weapons, some funneled through Qatar and Saudi Arabia, they have started to tame the hulking beast of war. 
 
 "Six or seven months ago, we didn't have anti-tank weapons; now we do, and it has changed things for us," said Hamza Sawa, a defector from the Syrian army who destroyed the tank with a rocket-propelled grenade. "We already had the fighters ready, but now we have the weapons too." 
 
 But even as the rebels make advances in their firepower and gain territory, serious divisions and suspicion among the fighters threaten to hold them back. 
 
 The civilians who launched the armed rebellion and the army defectors who have increasingly joined them both claim to be the true leadership of the offensive. The tension raises questions not only for the battle in Aleppo and elsewhere but for the chances of a smooth transition in any post-Assad period. 
 
 Perhaps just as ominous for the opposition, each time the rebels advance militarily, the Assad government uses another weapon in its arsenal, which increasingly includes attack helicopters and MiG fighter jets that rain down rockets on civilians and rebels alike, and the opposition has little ability to bring them down. 
 
 On Thursday, rebels, hampered by the barrage from the skies and an ammunition shortage, made a partial withdrawal from the strategic district of Salahuddin. But rebel commanders said they continued to seize more neighborhoods and now controlled more than half of Aleppo, a city once considered immune to the violence that has shattered much of the country. 
 
 In a large empty lot in an opposition-held part of the city sits another army tank that Assad's men have lost, but this one is still functioning. The rebels keep it mostly hidden under a beige tarp to avoid detection by government helicopters. 
 
 On a recent day, Col. Abduljabbar Aqidi, an army defector who heads the newly formed Aleppo Military Council, drove into the city with a small convoy. It felt a bit like a political campaign as he grabbed a Kalashnikov rifle, thanked rebels for their duty and posed with them for photos. At one point, in the Bab al-Hadid neighborhood, Aqidi stood on top of a fallen poster of Assad as he shook hands with children. 
 
 Behind him, a wall that once formed part of the original city had been repeatedly spray-painted with the words "Al Tawheed Brigade." The name of the group, which includes most of the militias fighting here, seems to cover most surfaces in rebel-controlled neighborhoods, as if a tagger were trying to make up for lost time. 
 
 Even Aqidi's white truck had "Al Tawheed Brigade" written in black marker on the side, as both a provocation to the government and a show of unity. 
 
 Unlike Aqidi's military council, the brigade consists of militias and opposition figures who were at the forefront of the revolution when it began last year. Military officers such as Aqidi didn't begin defecting in significant numbers until almost a year into the uprising. 
 
 Abdulaziz "Abu Jumuah" Salameh, who heads the Al Tawheed Brigade, works from the basement of a shot-up police station in Tal Rifaat, a town north of the city. He is dismissive of the newcomers' claims to leadership of the rebels, and most of the fighters here appear to belong to his brigade. 
 
 "The military council is an illusion," he said. "Now that weapons are coming in through them, they are trying to parlay that into power on the ground. We have been on the ground for a year and a half; the military council has been here for less than a month." 
 
 Aqidi was in the army for 29 years, and it shows in his ramrod posture. But he describes himself as more of a politician than a military man. 
 
 He defected this year and was in exile in Turkey until returning to Syria several weeks ago. Once he was on the front lines, money from the exile Syrian National Council and the Free Syrian Army that had been going to individual militias began flowing through him as a way to centralize the finances under one command. 
 
 That has created resentment. 
 
 A two-story elementary school in the Sakhour neighborhood has been transformed into a base of operations for the local militias here. As Aqidi walked in past murals recounting more peaceful times, a rebel was pushing a detainee into a hallway closet to "make him behave." 
 
 In an office with worn green velvet chairs, Aqidi met with the leaders and other members of militias that have sent hundreds of fighters flooding into Aleppo. One man from Tal Rifaat made an angry and impassioned plea for more ammunition. ||||| Syrian rebels captured a helicopter base just outside Damascus Sunday in what an activist called a "blow to the morale of the regime" near President Bashar Assad's seat of power, while the bombardment of a village near the capital killed at least eight children. 
 
 In this image taken from video obtained from the Ugarit News, which has been authenticated based on its contents and other AP reporting, Syrian rebels capture a helicopter air base near the capital Damascus... (Associated Press) 
 
 In this image taken from video obtained from the Ugarit News, which has been authenticated based on its contents and other AP reporting, Syrian rebels capture a helicopter air base near the capital Damascus... (Associated Press) 
 
 Activists said the children were killed when Syrian warplanes bombed the village of Deir al-Asafir just outside the Damascus. The village is close to suburbs of the capital that has been witnessing clashes, shelling and air raids between troops and rebels over the past months. 
 
 The Britain-based Syrian observatory for Human Rights said the bombardment of the village killed eight children. Another activist group, the Revolution Command Council said 10 children were killed when warplanes struck the village as they played outdoors. 
 
 An amateur video showed two girls lying dead in a street while the bodies of two bloodied dead boys were in the back seat of a car parked nearby. Several other wounded children were seen rushed for treatment. 
 
 Another video showed the bodies of two dead boys inside what appeared to be a makeshift hospital as others received treatment from injuries while lying on the floor. 
 
 The activist videos appeared genuine and corresponded to other AP reporting about the events depicted. Syria restricts the access of reporters. 
 
 Syria's conflict erupted in March 2011 with an uprising against Assad's regime, inspired by other Arab Spring revolts. It quickly morphed into a civil war that has since killed more than 40,000 people, according to activists. Hundreds of children have been killed since the crisis began, according to activists. 
 
 The air base takeover claim showed how rebels are advancing in the area of the capital, though they are badly outgunned, making inroads where Assad's power was once unchallenged. Rebels have also been able to fire mortar rounds into Damascus recently. 
 
 The director of the Observatory, Rami Abdul-Rahman, said rebels seized control of the Marj al-Sultan base on the outskirts of Damascus on Sunday morning. He said at least 15 rebels and eight soldiers were killed in the fighting that started a day earlier. The rebels later withdrew from the base. 
 
 Rebels appear to be trying to take over air bases and destroy aircraft in order to prevent the regime from using them in attacks against opposition forces around the country. 
 
 The rebels have no protection against the attack helicopters and fighter jets that have been blasting their positions. 
 
 Rebels have been attacking air bases in different parts of Syria, mostly in the northern regions of Idlib and Aleppo. 
 
 In the battle at the base outside Damascus, Abdul-Rahman and Damascus-based activist Maath al-Shami said rebels destroyed two helicopters with rocket propelled grenades and captured a tank. They say the base, which is on the eastern outskirts of Damascus, houses several radar positions. 
 
 "This is a blow to the morale of the regime, because it is close to the heart of the capital," said Abdul-Rahman, referring to the base that is about 15 kilometers (10 miles) from Damascus. 
 
 Al-Shami said the rebels withdrew from the base after they captured some ammunition. He said they feared counterstrikes by regime aircraft. 
 
 An amateur video posted online showed rebels walking next to two destroyed helicopters. At least three other helicopters appeared undamaged. Black smoke billowed in the distance. 
 
 Another video showed several radar posts on hills inside the large compound. Parked military trucks stood inside as rebels roamed freely. 
 
 The Observatory also reported violence in other parts of Syria, including the country's largest city of Aleppo in the north and the capital itself. 
 
 It said rebels on Sunday captured a training base for the Popular Front for the Liberation of Palestine-General Command near the Damascus suburb of Douma. The PFLP-GC is one of the Palestinian factions most loyal to Assad. 
 
 The PFLP-GC said in a statement late Saturday that the base was under attack. It said that thousands of activists and fighters who fought against Israel were trained at the base over the past 30 years. 
 
 Also Sunday, the Observatory said a bomb targeted a bus in the southern village of Othman, killing at least five people and wounding dozens. It said rebels and troops clashed in the southern region of Quneitra on the edge of the Israeli-occupied Golan Heights. 
 
 The Local Coordination Committees, another activist group, said residents found 12 bodies in the Damascus suburb of Daraya, scene of heavy clashes between rebels and government troops over the past few days. 
 
 State TV said troops clashed with al-Qaida militants in Daraya, killing some of them and confiscating a mortar that they were using in their attacks. 
 
 The station said that troops killed an al-Qaida affiliated Palestinian militant known as Abu Suhaib in the Damascus suburb of Hajira. It said his group was behind several bombings in Syria that killed and wounded dozens of people. 
 
 Assad's regime blames the revolt on a foreign conspiracy. It accuses Saudi Arabia and Qatar, along with the United States, other Western countries and Turkey, of funding, training and arming the rebels, whom it calls terrorists. ||||| Photo Advertisement Continue reading the main story 
 
 ANTAKYA, Turkey — For months, the disparate militias known as the Free Syrian Army relied on defections from the Syrian military to lead a credible if halting challenge to the government of President Bashar al-Assad. Every day seemed to bring word of new recruits. Soldiers fled in packs, or officers stole across a border, lifting the rebels’ morale while swelling their ranks. 
 
 
 
 
 
 
 
 
 
 But now opposition commanders say defections have slowed to a trickle. Some commanders have given up trying to entice defectors, and others have resorted to more desperate measures: cajoling, duping, threatening and even drugging and kidnapping military men to get them to change sides, or at least stay out of the fight. Without defections, they say, the opposition cannot hope to grow, never mind prevail. 
 
 “We use means only used by the devil,” said Ahmed Qunatri, a rebel commander in northern Syria who defected from the Republican Guard. 
 
 As Syria’s fighting burns into its 19th month, Mr. Assad’s forces have moved effectively to cut off what amounts to the armed rebellion’s most significant resource: soldiers with training and weapons who change sides. In a shift in strategy, the government has preferred to attack towns and neighborhoods from a distance using artillery and air power, preserving its resources and distancing its soldiers from rebel fighters — and from the public, including friends and neighbors, who might encourage defections. 
 
 Some rebel commanders now fret that all the soldiers who were inclined to defect already have. The rest remain loyal to the government, or are terrified of betraying it. Others are just suspicious of an armed movement that has found extremists among its ranks. A suicide attack in Aleppo on Wednesday that killed more than 40 people and devastated a government-held district drew widespread anger. Aware of just how much the violence is undermining popular support for the uprising, some rebel groups immediately tried to blame the government for staging the bombing. The government blamed the rebels. By nightfall, Jabhet al-Nusra, an insurgent group affiliated with Al Qaeda, claimed responsibility for the suicide bombings. 
 
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 Col. Qassem Sa’adeddine, the head of the rebel military council for Homs, said in an interview in Turkey that the government’s close watch, especially at checkpoints, meant “communicating with officers has become much harder.” The colonel said it had also become more difficult to protect the families of defectors — for example, safe houses were harder to come by in neighborhoods depopulated by the government. “The officers are more hesitant these days,” he said. More and more, he said, the rebels used force. 
 
 “We arrest them and give them a chance to defect,” he said. “Some are convinced after a week, so they are welcomed.” Those who remained unconvinced — loyal to the government — were imprisoned, he said, and would face a “trial.” 
 
 Some of the methods used by the rebels reflected a cunning forged in necessity, but also an ability, at times, for brutality. Several times in recent months, rebel fighting groups — making no effort to persuade their enemies — have been accused of summarily executing captured soldiers. Last week, rebel fighters claimed credit for bombing a school they said was used as a military base. “The fewer the defectors, the less the opposition strives to attract soldiers rather than just fight them,” said Peter Harling, an expert on Syria with the International Crisis Group. “And the harsher armed groups treat the enemy, the fewer will change sides. It’s a self-reinforcing dynamic.” 
 
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 Several commanders said they were still trying to persuade. Mr. Qunatri, the rebel commander, said in an interview here in Antakya that he preferred sending innocent-seeming emissaries to soldiers at military checkpoints. A 12-year-old boy, for example, helped turn one soldier, teasing him mercilessly until he relented. “Dude, why don’t you defect,” the boy would scold, repeatedly, as if the heavily guarded checkpoint was a schoolyard. 
 
 Another rebel officer, who uses the nom de guerre Abu Ali, sent a barber, Walid, who made friends with the soldiers by offering haircuts or doing laundry. “They want to defect,” Abu Ali said. “They don’t know how, or who can help.” 
 
 Another rebel commander who was a merchant before the war said he once sent a shepherd, who wandered by checkpoints and lent a sympathetic ear to the soldiers. “It helps if the soldiers were shepherds as well,” the commander said. “Nostalgia.” 
 
 Another of the former merchant’s operatives, a food delivery man, identified six recruits, but the checkpoint they guarded was too well secured for them to leave: there was no way past the officers. “We thought of sending sleeping pills,” the commander said. The recruits spiked the water and the tea. “Thirty-eight soldiers fell asleep,” said a soldier named Shadi, one of those who defected that day. Rebel seized the sleeping soldiers along with their weapons. Some willingly flipped and others were made to promise they would not return to the fight, he said. “Two of the 38 returned to the army,” he said. 
 
 Though the rebels claim to have attracted thousands of recruits, there is little evidence the defections have slowed the Syrian Army. Many rebels say they are still waiting for a pivotal moment, for instance, when a brigade changes sides. Until that happens, they say, they are squeezing the army of every last dissenter against increasing odds. 
 
 An officer from Damascus said rebels called him for 16 months, without ever giving their names, first peppering him with friendly requests, before telling him he would be killed if he did not desert. To drive home the point, sometimes, they called from dead soldiers’ cellphones. “I finally defected, but I was so scared I didn’t trust my own wife,” said the officer. 
 
 A few weeks ago, three Syrian border guards decided to flee the country, forcing another soldier who had no desire to defect with them at gunpoint, fearing he would thwart their escape. “It was very confusing,” the soldier said in a phone interview from a country neighboring Syria on Friday. “If I stayed, the officers would blame me and I would surely face the death penalty. If I refused, my colleagues might kill me.” 
 
 After they had crossed the border, the defectors told the soldier he was free. “But where to go?” the soldier said. “I’m stuck with no way to go back. I’m already involved.” Since his exile started, he had started to sympathize with the rebels, he said. 
 
 Such tactics have angered some antigovernment activists, who worry that they alienate supporters of the uprising. One activist, who requested anonymity for fear of angering the Free Syrian Army, cited a recent case that he said was part of a worrying trend: an officer from the coastal city of Latakia was kidnapped, thrown in the trunk of a car and told he was defecting or he would be killed. 
 
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 But faced with the government’s cruelty, many defectors said they needed no convincing: they were haunted, they said, by innocent victims and the cities they helped destroy. They spoke with pride about protecting demonstrations and defending their homes. 
 
 As the uprising has transformed into something more ambiguous — a struggle against a dictator but also a war scarred by sectarianism and foreign meddling — allegiances have become more contested. This week, in a jarring turn for the rebels, a man claiming to be a former insurgent commander appeared at an opposition conference in Damascus and said he was defecting back to the government. 
 
 “The solution in Syria does not lie in the use of weapons or violence or sabotage and explosions or the killing of innocents,” the commander, Col. Khaled Abdel-Rahman al-Zamel, said at the opposition meeting in Damascus. A spokesman for the Free Syrian Army asserted that the reversal was a ruse: the government had arrested the colonel back in March. “He is our colleague and our friend,” the spokesman said. ||||| Media playback is unsupported on your device Media caption Unverified video posted by opposition activists purportedly showed cluster bombs in Deir al-Asafir and rebels in Marj al-Sultan military base 
 
 Activists in Syria say a government jet has dropped a cluster bomb on a playground, leaving 10 children dead. 
 
 Video posted on the internet showed children's bodies on the ground with their mothers grieving over them. 
 
 The children were killed when a MiG fighter bombed a playground in the village of Deir al-Asafir, east of Damascus, opposition activists said. 
 
 Intensive fighting has continued around the capital. Rebel fighters captured at least part of an airbase on Sunday. 
 
 Further footage of the playground attack showed what appeared to be cluster bomblets on the ground. 
 
 In one video, two girls could be seen lying dead in a street while another showed a distraught mother standing, apparently inside a clinic, over her daughter's lifeless body. 
 
 The International Red Cross (ICRC) said it had been unable to confirm the attack. 
 
 But it said if such an attack had taken place, it would be a very serious incident as under the Geneva Convention, only military targets are legitimate. Civilians, and civilian buildings like schools and hospitals, should never be attacked. 
 
 In recent months there have been mounting allegations that the Syrian government has resorted to using cluster bombs as the conflict intensifies, although those claims have been denied, the BBC's Jim Muir in neighbouring Lebanon reports. 
 
 'Baseless' 
 
 Two cluster bombs were dropped on the village on Sunday, activists said. One man told Reuters news agency that 70 bomblets had been found. 
 
 "None of those killed was older than 15 years old," Abu Kassem, an activist in Deir al-Asafir told Reuters. 
 
 Analysis Almost imperceptibly, the armed revolt against the Syrian regime has morphed into something very different from the sporadic hit-and-run raids by ragtag bands of rebel fighters that prevailed until a few months ago. Now, strategically important regime bases and installations are encircled and besieged by rebel forces, sometimes for weeks on end, and some have been overrun. They include, most recently, the air base at Marj al-Sultan east of Damascus, and the highway-carrying Tishreen dam east of Aleppo. Before that, an artillery compound at Mayadeen on the Euphrates upstream from the Iraqi border, and the 46th regiment base to the west of Aleppo. Sometimes, for fear of air strikes, the rebels withdraw after disabling helicopters or other regime assets, and seizing arms, ammunition and vehicles. But little by little, the regime's grip is slipping. It is becoming clear that it lacks the dependable manpower to garrison outlying areas. Increasingly, it's falling back on its two big strongholds, Aleppo and Damascus, and lashing out with heavy artillery and air strikes which cause damage and casualties (often civilians), but don't change the strategic situation on the ground. But it could still be a long way to go before a tilt point might lead to a rapid collapse. And the regime continues to enjoy the vital support of Russia and Iran, who insist that President Bashar al-Assad must stay until a political transition is negotiated. 
 
 He said 15 people had been wounded in the attack and denied that rebel fighters were inside the village. They had been operating on the outskirts, he said. 
 
 Last month, Human Rights Watch said there had been an increase in online video reports purporting to show evidence of cluster bombs being dropped in the conflict, especially around the town of Maarat al-Numan. 
 
 The Syrian government said the military did not have such weapons and dismissed the allegations as "baseless". 
 
 An unverified report by the Local Co-ordination Committees (LCC), an opposition activist network, put the number of casualties across Syria on Sunday at 117, including 14 children. 
 
 The ICRC has issued a statement warning that the violence in Syria is intensifying and urged all those fighting to respect the lives of civilians. 
 
 It said more and more people are trapped by fighting in which it claims the protagonists are making little distinction between soldiers and civilians. 
 
 The organisation also warned that thousands of families are struggling to find basics like food, water, and medical care. 
 
 Activists believe 40,000 people have died since the start of protests against President Bashar al-Assad's rule in March 2011. 
 
 The UN refugee agency says the number of Syrians refugees in neighbouring countries either registered or awaiting registration has reached 442,000. Another 2.5 million are described as internally displaced. 
 
 Syrian government planes attacked a rebel headquarters close to a refugee camp near the Turkish border on Monday. No-one was hurt, but the attack caused panic among refugees at the Atma camp. 
 
 Battle for military bases 
 
 Rebel fighters said on Sunday they had captured a military airbase at Marj al-Sultan, not far from Deir al-Asafir, although activists of the UK-based Syrian Observatory for Human Rights said they had later pulled out. 
 
 Amateur video showed a rebel standing beside a wrecked helicopter while a man speaking on the video said a warplane had been blown up. 
 
 Although the rebels control areas to the east and north-east of Damascus as well as on the edge of the city, government forces are widely seen as superior in the capital and the Free Syrian Army has been unable to take permanent control of military bases. 
 
 Image caption The Russian prime minister said that the recognition of Syria's opposition coalition was 'unacceptable' 
 
 A similar rebel attack took place last week on an air defence battalion base at Hajar al-Aswad, south of Damascus, which fighters briefly controlled after a four-day siege. 
 
 The rebels have been more successful in holding on to bases in areas of Syria more firmly under their control. Last week opposition sources said they had seized a base at Mayadeen in the eastern province of Deir al-Zour. 
 
 They now appear to hold a swathe of territory in the Euphrates valley, from the Iraqi border to the provincial capital of Deir al-Zour. 
 
 Unverified videos posted on the internet on Monday showed fighters claiming to be in control of the Tishreen dam on the Euphrates river, further north in Aleppo province. There has been fierce fighting in the area around the dam for several days. 
 
 In a separate development, Russian Prime Minister Dmitry Medvedev has criticised a decision by France and the UK to recognise Syria's new opposition coalition as sole legitimate representative of the Syrian people. 
 
 "From the point of view of international law, this is absolutely unacceptable," he told French journalists ahead of a two-day visit to Paris, which was starting on Monday. 
 
 "A desire to change the political regime of another state by recognising a political force as the sole carrier of sovereignty seems to me to be not completely civilised." 
 
 The EU has stopped short of full recognition, describing the National Coalition for Syrian Revolutionary and Opposition Forces as "legitimate representatives of the aspirations of the Syrian people." 
 
 How a cluster bomb works 
 
 1. Cluster bombs are usually dropped from a plane and can fly several miles before releasing their load of bomblets. 
 
 2. The canister starts to spin and opens at an altitude between 1,000m and 100m, spraying the bomblets across a wide area. 
 
 3. Each bomblet is the size of a drink can and contains hundreds of metal pieces. When it explodes, it can cause deadly injuries up to 25m away.
– This could change things: Some Syrian rebels now have antiaircraft missiles, rebels and regional officials say. Video footage appears to show the rebels using such weapons, which have been smuggled into the country, the Wall Street Journal reports. Rebels say they downed a military helicopter yesterday, one of at least four aircraft reportedly shot down this week—if true, that's a quicker pace since the summer, although it's not clear how the copters and jets were brought down. Despite the fact that this could be good news for the rebels, it's bad news for the US, which worries such weapons could end up with anti-Western militias. More from Syria: The rebels today blew up one oil pipeline and one gas pipeline near Deir al-Zour, the AP reports, citing state media. Meanwhile, at least 20 people were killed in government airstrikes on rebel areas last night and this morning, activists say. Though Syrian President Bashar al-Assad has tried to shield Damascus, war has now reached the capital, the New York Times reports. The fighting isn't as intense as in other cities like Aleppo or Homs, but it's drastically increased since a few months ago: Checkpoints abound, kidnappings are common, bombings are increasing, and it's not safe to go out after dark. "How soon before our city, our markets, are destroyed?" wonders one resident. Similarly, Syria's wealthy—many of whom back the president—are now seeing their businesses hurt by the war, and some are losing faith in Assad, the AP reports. Many have seen factories burned or otherwise affected by fighting, and others have had their money restricted by sanctions. Yet more trouble for Assad: Even his own sect, the Alawite minority, is growing discontent, the Washington Post reports. Alawites had been strong backers of Assad, as the Sunni majority backed the rebellion, because they feared losing power to Sunni Islamists. But, though there is no indication that Alawites plan to join the rebellion, there are reports of rifts even within Assad's own extended family.