BEIRUT: More than 500 rebels and government forces have been killed in one week of fierce fighting to control the Syrian city of Aleppo, activists said on Saturday.
The Syrian Observatory for Human Rights said the majority of those killed since July 31 were rebels fighters and extremists "because of the aerial superiority of the regime and intense Russian airstrikes."
Observatory chief Rami Abdel Rahman said at least 130 civilians had also been killed since Sunday, most in rebel shelling of government-controlled districts.
He said at least seven civilians were killed on Saturday in rebel shelling of the government-held neighborhood of Hamdaniyeh.
Government forces on Saturday struggled to push back a powerful assault on military positions south of the battleground city.
The offensive has brought together rebels, Islamists and extremists in an attempt to cut off a government route into Aleppo and break the government siege of eastern districts.
Anti-government forces have captured the armaments school and most of the artillery school at a large military academy, bringing them closer to the government's access route into the city.
The former Nusra Front - renamed Jabhat Fateh al-Sham after breaking from Al-Qaeda - on Saturday announced having captured the two military schools and a third military position.
Drone footage posted by the group online showed a series of explosions in some of those buildings, and massive columns of billowing black smoke.