JERUSALEM (JTA) — An airstrike on Damascus that is being blamed on Israel killed five Iranian-backed fighters, a watchdog group reported.

The attack on Monday night destroyed a missile depot and hit military positions, weapons and ammunition warehouses in the Syrian capital, according to the Syrian Observatory for Human Rights, which is based in the United Kingdom.

It is not known if the dead fighters were Iranians or members of Iranian-backed groups from other countries.

Four other foreign fighters and seven members of Syria’s Air Force also were injured in the attack, two seriously, according to the report.

The state-controlled Syrian Arab News Agency, or SANA, reported that Syrian air defenses were able to shoot down the majority of the missiles fired during the “Israeli aggression.” It quoted an unnamed military source as saying that “the aggression led to the injury of seven soldiers and caused material damages.”

Israel neither confirmed nor denied the airstrikes, though it is believed to have carried out dozens of airstrikes on Syria. Syria has accused Israel of at least eight airstrikes on its territory in the past two months, the last on June 28, according to Haaretz.