Pro-government forces have hit back after rebels seized parts of Syria's economic capital, Aleppo, and tried to move into its historic old city.
Fighter jets and helicopters attacked targets in the east of the city and reports said thousands of troops were being moved to counter the threat.
Dead and wounded civilians and fighters were taken to hospitals and makeshift clinics as the human cost of this conflict continues to grow.
A general and former aide to President Assad has appeared publicly for the first time since he fled this month.
Brig-Gen Manaf Tlas confirmed he had abandoned the Syrian government.
Brig-Gen Tlas's decision to abandon Bashar al-Assad had been seen as significant as he had commanded the 10th Brigade of the elite Republican Guard and was an important Sunni figure in the president's inner circle.
He had kept silent for 18 days, raising questions of whether he had defected to the opposition or merely fled.
His whereabouts is still unclear.