DAMASCUS, Sept. 19 (Xinhua) -- Syrian President Bashar al-Assad on Wednesday offered condolences to his Russian counterpart Vladimir Putin for the death of Russian soldiers during a recent Israeli missile attack on Syria, state news agency SANA reported.

While offering his sincere condolences, Assad blamed the death of the Russian soldiers on the "Israeli smugness and arrogance."

On Monday evening, a Russian military aircraft with 15 Russian personnel onboard was mistakenly downed by a Syrian missile while the Syrian air defenses were responding to an Israeli missile strike that targeted Syria's Latakia province and lasted for one and a half hour.

The Russian Defense Ministry said a missile from Syria's S-200 air defense system shot down the Il-20 surveillance plane with Russian servicemen by mistake because an Israeli airstrike took place at the same time, blaming a simultaneous Israeli strike as the cause of the mistake.

The aircraft, which was on its way back to the Russian-run Hmeimim air base, disappeared from the radar on Monday night at a time when four Israeli F-16 fighters attacked targets in Syria's Latakia province.

The incident marked the first mistake strike between Syria and Russia, which is the main ally to the Syrian government.

"On behalf of the Syrian people and by my name, we express our deep condolence over the fall of the Russian jet on the Mediterranean, causing the martyrdom of the Russian heroes who were doing their noble duties along with their colleagues of the Russian military forces in the fight against terrorism in Syria," Assad said in his letter of condolences to Putin.

"We are confident that such painful acts would not affect you and us to continue fighting terrorism," Assad said.

Israel has carried out some 200 airstrikes over the last 18 months, claiming that the attacks aimed to prevent Iranian weapons convoys and stop Iran from establishing a military foothold in Syria.