READ MORE: Iran's Media Reports Israeli Plans to Escalate Missile Strikes on Syria (VIDEO)

Russian defence ministry also said that an Il-20 aircraft with 14 people on board disappeared from the radars of aviation control during an attack of four Israeli F-16 aircraft on Syrian targets in the province of Latakia. "Connection has been lost with the crew of a Russian Il-20 plane over the Mediterranean Sea 35 kilometers from the Syrian coast as it was returning to the Hmeimim airbase," the Russian defense ministry said early Tuesday, September 18. According to Sana news agency, the military said it had intercepted "enemy missiles coming from the open sea towards the city of Latakia". The IDF also says that the Russian plane was not "within the area of operation" while the Israeli strike on Latakia was underway. A search-and-rescue source told the Interfax news agency that the Russian warplane could have sunk in the Mediterranean Sea as a result of an "unforeseen critical incident" in the air. The ministry said that the jet had gone off the radar around 11pm Monday (local time) during an attack by four Israeli F-16 jets over Syrian infrastructure in the province of Latakia, a stronghold of president Bashar al-Assad. RIA Novosti news agency, citing a security source, said that Syrian anti-defence systems had countered a rocket attack. The Israeli government is concerned by what it calls Iran's "military entrenchment" in Syria, as well as shipments of Iranian weapons to the Lebanese militant group Hezbollah, which is fighting alongside Syrian government forces. An Israeli military spokeswoman when asked about both the reported Israeli strike and the Russian plane said: “We don’t comment on foreign reports.”

A Pentagon spokesman said the United States was not involved and declined to provide further details. The IDF alleges that by the time Syrian antiaircraft missiles had been launched, Israeli warplanes responsible for the overnight operation were already back within Israeli airspace. The Russian defence ministry also said that rockets had been launched from the French Navy's frigate, The Auvergne, which was in the area at the time. "The French army denies any involvement in this attack," a French army spokesman said. Demilitarized zone in neighboring Idlib

The incident occurred on the same day that Russia announced a joint agreement with Turkey to create a demilitarized zone in Syria's Idlib province, which neighbors Latakia, potentially thwarting a large-scale military operation and impending humanitarian disaster in the country's last rebel stronghold. After more than four hours of talks with Russian president Vladimir Putin at his residence in the Black Sea resort of Sochi, Turkish leader Recep Tayyip Erdogan said their two countries would “prevent a humanitarian tragedy.”

Putin said the two leaders agreed to create a 15-20 kilometre-wide demilitarised zone along the line of contact between rebels and regime troops by October 15. This would entail a "withdrawal of all radical fighters" from Idlib including the Al-Nusra Front and also the withdrawal of heavy weaponry including tanks, multiple launch rocket systems, Putin said. In recent weeks, Syrian and Russian planes have conducted scores of airstrikes in Idlib in the run-up to an anticipated offensive by Russian-backed Syrian forces to retake the last part of the country under armed opposition. Russia intervened in the Syrian conflict to buttress the Assad regime in 2015. Russia has previously lost aircraft during its Syria campaign. In November 2015, Turkey shot down a Russian warplane near the Syrian border, triggering a severe crisis in ties with Moscow.
A Russian Air Force Ilyushin Il-20 reconnaissance plane with 14 servicemen on board disappears from radar over the Mediterranean Sea during the missile attack on Syria's Latakia Governorate. A U.S. official claims the Syrian Army inadvertently shot it down while attempting to intercept missiles, while Russia detected a missile launch from a French FREMM multipurpose frigate.