Free Syrian Army soldiers continue to fight to control the city of Aleppo 0108122

Conflict in the World - Syria War

A member of the Free Syrian Army flashes the victory sign on a captured tank after taking control of a checkpoint from government forces in Anadan, north Aleppo, July 31, 2012.

During the day yesterday large clouds of black smoke rose into the sky after attack helicopters turned their machineguns on eastern districts for the first time in the latest fighting and a MiG warplane later strafed the same area.

A rebel commander in Aleppo said his fighters' aim was to push towards the city centre, district by district, a goal he believed they could achieve "within days, not weeks".

"The regime has tried for three days to regain Salaheddine, but its attempts have failed and it has suffered heavy losses in human life, weapons and tanks, and it has been forced to withdraw," said Colonel Abdel-Jabbar al-Oqaidi, head of the Joint Military Council, one of several rebel groups in Aleppo.

The battle for Aleppo, Syria's largest city, has become a crucial test for both sides in the 16-month-old rebellion. Neither Assad's forces nor the rag-tag rebels can afford to lose if they hope to prevail in the wider struggle for Syria.

According to an NBC News report that a Western official did not dispute, the rebels have acquired nearly two dozens surface-to-air missiles, which were delivered to them via neighbouring Turkey. The analysis of the video by Army Recognition team released by NBC News, the anti-aircraft missiles would be Russian-made SA-7 Grail.

It is not clear what kind of man-portable air-defence systems they are or whether the rebels have the training to use them, but the missiles could tilt the fighting field if the rebels were able to target the Syrian government's air operations.