Syrian opposition activists say government warplanes have bombed a Palestinian camp on the southern outskirts of the capital, Damascus, killing at least eight people.

The activists said Sunday's air strike was the first of its kind on the Yarmouk refugee camp since forces loyal to President Bashar al-Assad began suppressing a popular uprising in March 2011. They said at least some of those killed were in a mosque struck by a missile.

The Britain-based Syrian Observatory for Human Rights said the Yarmouk raid was one of six government air strikes on southern areas of Damascus on Sunday. Rebels have been trying to advance from those areas into central Damascus, the seat of Mr. Assad's power.

Elsewhere, an Islamist rebel faction claimed to have seized an army academy near the northern city of Aleppo after days of fighting with government troops. The Tawheed brigade posted a video on its website Sunday, showing fighters walking around the base, while exchanges of fire could be heard in the background.

The army academy appears to be the latest Syrian military installation to fall to the rebels this month around Aleppo, Syria's commercial capital.

At the Yarmouk camp, the Observatory said fighting erupted after the air strike, with Syrian rebels and their Palestinian allies battling a Palestinian faction loyal to Mr. Assad, the Popular Front for the Liberation of Palestine-General Command (PFLP-GC). Syria is home to hundreds of thousands of Palestinian refugees and their descendents, whose loyalties have been divided by the Syrian civil war.

There was no independent confirmation of the casualties at Yarmouk or the fighting at the military academy because Syria bars independent journalists from reporting freely.