Airstrikes targeting positions of Iran-backed militias in eastern Syria killed nine fighters Sunday in the second such raid in 24 hours, The Syrian Observatory for Human Rights said.
The war monitor said Israel was "likely responsible" for the strikes near the Iraqi border, which came hours after a similar raid killed six other Tehran-backed fighters, raising the toll to 15 killed in 24 hours.
The fighters killed in the early Sunday raids were mostly Iraqi nationals, according to Observatory head Rami Abdul Rahman.
Israel has launched hundreds of strikes in Syria since the start of the war in 2011.
It has targeted government troops, allied Iranian forces and fighters from Lebanon’s Hezbollah.
It rarely confirms details of its operations in Syria, but says Iran's presence in support of regime head Bashar al-Assad is a threat and that it will continue its strikes.
On Saturday, airstrikes also blamed on Israel hit positions belonging to regime forces and Iran-backed militias near the border with Iraq, the Observatory said.
Four Syrian nationals were among the six fighters killed in that attack, the monitor added.
Saturday's raids came only days after Israeli strikes in the eastern province of Deir Ezzor and the southern province of Suweida killed seven fighters, including two Syrian soldiers, according to the Observatory.
