"Israel targeted a building frequented by senior Revolutionary Guards and Hezbollah operatives, as well as a car parked in front of the building... killing four people," the Britain-based Syrian Observatory for Human Rights said.

Earlier, Syria's official SANA news agency reported an Israeli strike on a residential building in the Mazzeh neighbourhood of Damascus, which is home to security headquarters and embassies.

AFPTV footage from the scene showed a building engulfed in smoke, with rubble and torn metal strewn on the ground. An AFP correspondent counted about 20 cars damaged by the falling debris.