JERUSALEM (AFP) - Israel downed a drone over the occupied Golan Heights on Sunday, the army said, amid mounting tension on the UN-patrolled armistice line with Syria on the strategic plateau.

Air defences "successfully intercepted an unmanned aerial vehicle (UAV) that breached Israel airspace above the border with Syria," an army statement said.

Heavy fighting between Syrian government troops and opposition forces flowed into the buffer zone separating Syrian and Israeli-occupied territory at the weekend.

Dozens of Filipino UN peacekeepers escaped the hot zone overnight after rebels rammed their Golan Heights outpost with armed trucks, the Philippine military said.

Israel seized 1,200 sq km of the Golan Heights during the Six-Day War of 1967, then annexed it in 1981 in a move never recognised by the international community.

The UN Disengagement Observer Force has been monitoring the ceasefire since 1974.