With the Syrian capital in turmoil as a suicide bomb kills senior regime members and rebel forces mount an all-out assault, are we witnessing the end of the Assad regime?
A suicide bomb has killed the Syrian defence minister Daoud Rajiha and President Bashar al-Assad's brother-in-law Assef Shawkat, according to state media.
Other senior members of the regime have been critically injured in the attack on the National Security Building in the Rawda district of Damascus.
The news follows three days of violence in the Syrian capital, which the rebel Free Syrian Army has described as an all-out assault to liberate Damascus. Earlier there were reports of gunfire and plumes of smoke in a street near the parliament, the BBC reports.
Government forces have deployed helicopter gunships and tanks in Damascus for the first time. "Regime forces are threatening to bombard the whole area and telling civilians to evacuate their houses," an opposition activist in Damascus told The New York Times.
The British-based Syrian Observatory for Human Rights said that 16 people were killed in the capital yesterday. In the northern suburb of Qaboun, where fighting has been intense, activists reported that tanks were shelling homes and shooting "every moving thing".
There were also unconfirmed claims that an army helicopter had been shot down, Sky News reports. A senior rebel said: "Helicopters are flying at low altitude. It's easy to target them using anti-aircraft weapons."
Colonel Qassim Saad Eddine, a Homs-based member of the Free Syrian Army, told Lebanese TV that the "battle for the liberation of Damascus has begun", according to the Los Angeles Times. "We have a clear plan to control the whole of Damascus," he said. "We have only light weapons, but it's enough."
Adding to the sense of what the Free Syrian Army characterises as a final battle, The Financial Times reports that President Bashar al-Assad has redeployed troops from the Golan Heights, where it is engaged in a 45-year-old dispute with Israel, to Damascus.
An Israeli general told a Knesset committee yesterday: "The Syrian military is acting very brutally, which shows the regime is desperate. Its control of Damascus is getting weaker.
"Assad has moved many of his forces that were in the Golan Heights to the conflict areas."
However, many people, including some within the Free Syrian Army, are sceptical as to whether we are witnessing the end of the Assad regime.
Exiled activist Malik al-Abdeh said 'Operation Damascus Volcano', as the rebels have dubbed the assault, is probably just a morale-boosting exercise. "It looks more like a publicity stunt designed to make an impact and encourage more defections," he said in comments reported by The Guardian. "The FSA can't sustain this sort of battle for very long."
Abu Raed, a Free Syrian Army coordinator in Qaboun who was interviewed in Turkey said: "The battle for Damascus has not started. It is more ebb and flow; these skirmishes are just a test as our fighters infiltrate then withdraw."
Jim Muir of the BBC said there was no evidence of a helicopter being downed in the capital.
But even if this is not the endgame for Assad, the developments in Damascus are undeniably serious.
The redeployment of troops from their face-off in the Golan Heights with the old enemy Israel, appears to have become necessary because the Syrian army is now fighting to its fullest capacity.
Jeffrey White, a former Defence Intelligence Agency officer and specialist on the Syria military, told The New York Times that sustained combat between government troops and the rebels was now ongoing in nine of the country's 14 provinces. "The regime is now fighting a 360-degree war," he said, adding that all 13 of the Syrian army's combat divisions are engaged in action against the rebels.
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