Russia's Defense Ministry has said that one of its military aircraft "disappeared" over the Mediterranean during an Israeli air attack on Syria.

The Il-20 reconnaissance aircraft went down with 15 service members during an attack by four Israeli F-16 jets on the coastal city of Latakia, near the Hmeymim airbase to which the Russian plane was returning, the ministry said.

Read more: Syria conflict: What do the US, Russia, Turkey and Iran want? 

It also said it detected missile launches in the area from the French frigate Auvergne. In a statement, the French military has "denied any involvement in the attack."

US officials told CNN and Reuters that Washington believed Syrian air defenses had accidentally shot down the Russian aircraft. If true, it would be an embarrassment for Moscow to have one of its aircraft hit by its Syrian ally, which operates air defense systems provided by Russia. 

The Il-20 disappeared from radar at about 11 p.m. Moscow time (20:00 GMT) on Monday some 35 kilometers (22 miles) off the Syrian coast, the Russian Defense Ministry said. 

At around the same time, Syrian state media SANA reported that government air defenses had "intercepted hostile missiles coming from the sea into Latakia city."

Russia threatens to retaliate

The Technical Industry Institution on the outskirts of Latakia was reportedly targeted in the alleged Israeli attack. It was unclear if Syrian government or Iranian forces were at the facility. Michael A. Horowitz, a geopolitical and security analyst with Le Beck International, posted a video of the alleged airstrike.

Russian Defence Ministry spokesman Igor Konashenkov blamed Israel for indirectly causing the incident and said Russia reserved "the right to take commensurate measures in response," without giving further details.

"We view the actions of the Israeli military as hostile," Konashenkov told Russian state television. "As a result of the irresponsible actions of the Israeli military, 15 Russian service personnel perished."

Israel rarely acknowledges carrying out specific airstrikes in Syria, but is believed to be behind dozens of attacks on Iranian forces and Hezbollah weapons shipments. Israeli officials have repeatedly stated they will not hesitate to target Iranian advanced weapons in Syria.

Read more: What is Iran's role in Syria if Assad wins the war?

On Saturday, Syrian air defenses downed suspected Israeli missiles fired at the Damascus airport, state media reported.

Russia has generally turned a blind eye to Israeli attacks on Iranian forces in Syria and the two countries' militaries maintain a hotline to avoid mistakes. It is unclear whether the Israeli military notified Russia ahead of Monday night's attack in Latakia.

However, the downing of a Russian aircraft in the crowded airspace over Syria may alter Israeli military calculations and its ability to operate against Iran. 

cw,law/cmk (AFP, AP, dpa, Reuters)

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