The Russian Air Force's commander-in-chief said in an interview with Russian daily Komsomolskaya Pravda that Russia sent "anti-aircraft missile systems" to Syria to better protect its fighter planes engaged in daily airstrikes in the Middle East country.

"We have calculated all possible threats. We have sent not only fighter jets, bombers and helicopters, but also anti-aircraft missile systems," Colonel General Viktor Bondarev told the Russian daily Komsomolskaya Pravda.

Bondarev said there were many reasons for the decision, including the possibility of Russian combat aircraft being hijacked or attacked.

"There may be different kinds of force majeure. For example, the hijacking of combat aircraft in the territory of Syria's neighboring states to strike at us. And for this, we must be prepared," Bondarev added.

War on terrorism?

The statement comes after more than a month of Russian airstrikes in Syria, which the Kremlin says are aimed at destroying the Islamic State militant group.

Moscow has been accused by Western governments of propping up the regime of Syrian President Bashar al-Assad, which ignited a civil war when it cracked down on pro-democracy protesters in 2011.

Syrian rebels and activists claim that the strikes specifically target anti-Assad fighters, and rarely hit the militant group's sites.

However, Russia's defense ministry said on Tuesday that it reached out to opposition leaders in a bid to bolster cooperation in the fight against "terrorism," although it was unclear which rebel groups established contact.

Islamic State claims retribution

Meanwhile, the Islamic State on Wednesday reiterated claims that it downed a Russian civilian aircraft last week; a statement that the British foreign minister says could prove likely.

"If you think you can destroy our state by sending your planes, vehicles and soldiers, you are wrong and you will regret that," a Russian "Islamic State" militant said in a video, reported news site Vocativ.

"The plane we downed is the best proof. We will not be satisfied with downing your planes, but will storm your houses and will slaughter you."

ls/kms (AP, AFP, Reuters)