A Russian military surveillance plane with 14 crew members has disappeared from radar over the eastern Mediterranean Sea, Russia's Defense Ministry says.

The ministry said in a statement on September 18 that the Ilyushin Il-20 aircraft went off radar 35 kilometers from the Syrian coast at about 11 p.m. local time the previous day.

It said the plane was returning to Hmeimim air base in the northwestern Syrian province of Latakia, where the bulk of Russia’s armed forces in the country are stationed.

Russian military forces have launched a search operation.

It was not immediately clear whether the plane was shot down.

Russia has given Syrian President Bashar al-Assad crucial support throughout the Syrian conflict, which began with a government crackdown on protesters in March 2011.

Hmeimim is Russia's main base for air strikes on rebel groups in Syria.

The Ilyushin disappeared from radar at around the same time that Israeli F-16 fighters attacked Syrian facilities in Latakia Province, the Russian Defense Ministry said.

It also said rocket launches were detected from the French frigate Auvergne nearby around that time.

"The French Army denies any involvement in this attack," a French military spokesman said.

The Israeli military refused to comment on reports its planes targeted facilities in Latakia.

A Pentagon spokesman said the United States was not involved.

Unnamed U.S. official were quoted as saying Washington believed the Russian patrol aircraft was accidentally shot down with antiaircraft artillery by the Syrian government.

The Syrian government has not yet commented on the incident.

Earlier, the official Syrian news agency SANA reported that missiles were fired at several locations in Latakia Province late on September 17.

State media said the explosions were suspected to have been caused by Israeli strikes.

Meeting in Russia’s Black sea resort city of Sochi earlier on September 17, Russian President Vladimir Putin and his Turkish counterpart, Recep Tayyip Erdogan, agreed to create a demilitarized buffer zone in Syria's northwestern province of Idlib to separate government forces from rebel fighters based there.

Turkey is backing rebel groups in the Syrian war and has troops in the country’s north.

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