Syrian regime media said Israel hit a military position near Aleppo in the country's northwest, killing nine pro-regime fighters. The strike comes as the regime steps up its offensive against rebels in the country's southwest.
At least nine pro-regime fighters died in a suspected Israeli missile strike overnight in northern Syria, a monitor said on Monday.
The Syrian Observatory for Human Rights (SOHR), a Britain-based war monitor, said the base was being used by the Syrian regime's ally Iran.
"The Israeli missiles targeted an Iranian Revolutionary Guard centre, near the Neirab military airport," said Observatory head Rami Abdel Rahman.
He said those killed included at least six Syrians, but could not specify the nationalities of the remaining fighters.
"The Zionist enemy ... targets one of our military sites north of Nairab airport, causing only material damage," said Syrian state news agency SANA, quoting a military source.
An Israeli military spokesman declined to comment on the report.
Iran is a key ally of Syrian regime leader Bashar al Assad and backs a number of militias, including Lebanon's Hezbollah, fighting in support of Assad.
Late Sunday, state news agency SANA said Israeli missiles had hit near a strategic air base, but said there were no casualties.
The attack is the third suspected Israeli strike on Syria this month alone.
Israel has repeatedly warned it would not tolerate an entrenched presence of its arch-foe Iran in neighbouring Syria.
Israel has been on high alert in recent weeks as Assad's forces fight to retake parts of southern Syria bordering the Israeli-occupied Golan Heights.
Hundreds of Syrian rebels and their relatives are leaving the southern city of Daraa under a deal to bring the “cradle” of the country’s uprising back under regime control.
The transfers came as Russian-backed regime forces advanced in the neighbouring province of Quneitra, with air strikes pounding rebel positions perilously close to the Israeli-occupied Golan Heights.
TRT World's Sara Firth has more details.
After taking a majority of the key province of Daraa, government troops are waging an offensive on the adjacent province of Quneitra which remains mostly in rebel hands.
They began heavily bombing the area early on Sunday morning and air strikes continued there on Monday, according to the Observatory.