At least 66 people were killed Thursday as Syria's regime pounded a rebel stronghold with air strikes after a barrage of opposition fire hit the capital Damascus, a monitor said.
The Syrian Observatory for Human Rights said 12 children were among those killed in the opposition-held Eastern Ghouta region outside Damascus, and an AFP photographer there described chaotic scenes.
In the capital, meanwhile, a barrage of at least 120 rockets and mortar rounds fired by rebel forces killed 10 people, among them a child.
The fire left usually busy streets of the city deserted and prompted Damascus University to close for the day, sending students home.
The assault on the capital began early on Thursday and came two days after the leader of rebel group Jaysh al-Islam (Army of Islam) warned it would attack in response to repeated government strikes on rebel-held Douma in Eastern Ghouta.