At least 43 fighters died in clashes between the Syrian army and rebel brigades in the province of Quneitra, bordering on the Golan Heights, the Syrian Observatory for Human Rights said Sunday.

According to the statement released by the organization, forces of the Bashar al Assad regime and its allied militias lost 26 men during the clashes on Saturday.

Meanwhile, 17 combatants were killed from among the rebel brigades, including in particular the Al Nusra Front, an affiliate of Al Qaeda in Syria.

The fighting took place in the so-called central sector of Quneitra, where the insurgents several days ago launched an offensive.

Regime forces on Sunday also bombarded the area to try and halt the rebel advance, although at present there are no available casualty reports.

Syrian rebels - including the Free Syrian Army and the Al Nusra Front - announced their offensive three days ago, with its objective being to take control of several sectors in the central part of the province and around the city of Quneitra "with the aim of opening the way to Damascus."

The zone has been the scene of fighting since late August, when the insurgents took control of the only border crossing between Syria and the Israeli-occupied Golan Heights.

On Aug. 28, one day after the border crossing was taken, the Al Nusra Front captured 45 Fijian U.N. peacekeepers in the Golan Heights whom they have threatened to judge according to Islamic law. EFE