At least four pro-Iranian fighters were killed early Thursday in Israeli strikes on several positions near Damascus, a war monitor has said.

The latest wave of strikes is reportedly the third such attack in less than a week.

Israel has carried out hundreds of air strikes on Syrian territory since civil war broke out there in 2011, targeting government positions as well as allied Iran-backed forces and Hezbollah fighters.

Explosions were heard in the Syrian capital in the night of Wednesday to Thursday, an AFP correspondent reported.

"At around 00:30 am, the Israeli enemy carried out an aerial aggression from the direction of the occupied Palestinian territories targeting several positions in the vicinity of Damascus," the Syrian defense ministry had said in a statement.

Syria's air defense intercepted several missiles, the ministry added.

It did not provide any details on the targets and said that the strikes caused material damage.

The Israeli strikes targeted "weapons and ammunition depots and bases housing Iranian-backed groups a few kilometers from Damascus International Airport," the Syrian Observatory for Human Rights monitor said.

The U.K.-based war monitor, which relies on a wide network of sources in Syria, later said that four pro-Iran fighters, including one Syrian, were killed during the strikes.

On Monday, Israel struck the vicinity of Damascus, wounding one soldier, after a strike three days earlier targeted Syrian military sites near the airport.

While Israel rarely comments on the strikes it carries out on Syria, it has repeatedly said it will not allow its archfoe Iran to gain a foothold there.