Israeli strikes on Syria's Homs killed five people including three civilians Wednesday, a war monitor said, with Syria's defence ministry reporting an unspecified number of civilians dead.

"Five people have been killed including three civilians -- a woman, a child, and a man -- and seven others were injured in Israeli strikes on a building in the Hamra neighbourhood of Homs city," said the Syrian Observatory for Human Rights, updating an earlier toll of four.

The identities of the two non-civilian casualties were unknown, the monitor said.

Syria's defence ministry reported that "the Israeli enemy launched air strikes from the direction north of Tripoli (Lebanon) targeting a number of sites in the city of Homs and its countryside... killing and injuring a number of civilians".

Syrian state television shared footage of rescuers rummaging through the rubble of what appeared to be a collapsed building and carrying someone on a stretcher.

Earlier, Syrian state television reported "an Israeli assault" on central Syria, in Homs province.

Last week, the United States carried out strikes on Iran-backed groups in Syria and Iraq, killing dozens in retaliation for a deadly attack on its troops in Jordan.

Israel had also struck targets in Syria twice that week. On Friday, Israeli strikes killed three pro-Iran fighters south of Damascus, according to the Observatory, with Iranian media reporting an adviser from the Revolutionary Guards was among the dead.

Last Monday, Israeli strikes near Damascus killed eight people, including pro-Iran fighters, the Syrian Observatory for Human Rights had said.

During more than a decade of civil war in Syria, Israel launched hundreds of air strikes in the country, primarily targeting Iran-backed forces as well as Syrian army positions.

But such attacks have intensified since the war in Gaza between Israel and Hamas began on October 7.

Israel rarely comments on individual strikes targeting Syria but has repeatedly said it will not allow Iran, which backs President Bashar al-Assad's government, to expand its presence there.

Since 2011, Syria has endured a bloody conflict that has killed more than half a million people and displaced millions.