"An Israeli air strike targeted a flat in a residential building in the Mazzeh neighbourhood frequented by Hezbollah leaders and the Iranian Revolutionary Guards," the Britain-based Syrian Observatory for Human Rights said.

It killed at least three people, two of them foreigners, the monitor said.

State news agency SANA quoted a military source as saying that that "the Israeli enemy launched an air strike... targeting one of the residential buildings in the Mazzeh neighbourhood".

The source said three civilians were killed and three wounded.

Wednesday's strike hit around 500 metres (yards) from Tuesday's strike.

The Observatory said the earlier strike killed six people -- three civilians including a television anchor and three Iran-backed fighters, one of them from Hezbollah.

Israel has carried out hundreds of strikes in Syria since the country's civil war erupted in 2011, mainly targeting army positions and Iran-backed fighters, including those of Hezbollah.

Israeli authorities rarely comment on individual strikes but have said repeatedly they will not allow arch-enemy Iran to expand its presence in Syria.

The strikes have intensified in recent days, including in areas near the border with Lebanon.