"The missiles, probably Israeli" were fired at the southern region close to the Golan Heights, an area occupied and annexed by Israel, the Britain-based Syrian Observatory for Human Rights said.

The missiles targeted Tall al-Hara in Daraa province, south of Damascus, and two areas in the neighbouring province of Quneitrathe, it added.

"The regime's anti-aircraft defence has been activated to counter the attack," director of the Observatory Rami Abdel Rahmane said.

The Observatory reported "loss of life" without giving further details.

Syrian state television also referred to reports of "Israeli aggression" in the region.

Israel has carried out hundreds of air strikes in Syria since the beginning of the conflict in 2011, targeting forces loyal to President Bashar al-Assad and the regime's allies Iran and Hezbollah.

The Syrian conflict has killed more than 370,000 people and drawn in world powers since it started in 2011 with the brutal repression of anti-government protests.