Russia’s flagship state media channels Sputnik and  RT say the pilot of a Su-25 bomber shot down in Syria on February 3 blew himself up after he was surrounded by Islamist fighters.

The Russian Defence Ministry has confirmed that a Su-25 close-support aircraft was shot down over Syria and that the pilot was killed.

A ministry statement first said the pilot ejected from the aircraft but was killed while resisting capture by anti-regime rebels. The statement said preliminary evidence indicates the plane was shot down by a shoulder-fired anti-aircraft missile.

Reports from both RT (formerly Russia Today) and Sputnik – considered official propaganda mouthpieces for the Kremlin, known for wildly inaccurate reporting and stridently anti-Western conspiracy theories – are now spinning a story that claims Major Roman Filipov set off a grenade once he was surrounded by Islamist fighters.

Moscow announced that Filipov will be posthumously given the Hero of Russia award, the highest honorary title of the Russian Federation.

A jihadist group called Hayat Tahrir al-Sham claimed responsibility for the downing, saying a shoulder-launched missile had been used. The statement on the rebel-affiliated media channel Ibaa did not mention the Russian pilot.

According to Moscow-based newspaper Novaya Gazeta, Filipov was from Crimea, the Ukrainian Black Sea peninsula that Russia invaded and illegally annexed in 2014.

Vladimir Shamanov, chairman of the State Duma’s Defense Committee, seemed to hint that the US may have had a hand in the downing, saying, “There are over 1,000 US instructors in Idlib, so it could be a provocation.”

The US State Department said it was “deeply concerned” at reports of shoulder-launched anti-aircraft systems being used and denied the United States had ever supplied such weapons.

“The United States has never provided MANPAD missiles to any group in Syria, and we are deeply concerned that such weapons are being used,” spokeswoman Heather Nauert said.

“The solution to the violence is a return to the Geneva process as soon as possible, and we call on Russia to live up to its commitments in that regard,” she added.

Russia has been conducting military operations in support of close ally Syria dictator Bashar al-Assad, since September 2015.

The February 3 incident is the first where Syrian rebels have shot down a Russian warplane. In July 2016, rebels used a shoulder-launched missile to shoot down a Russian-made Syrian helicopter manned by a Russian crew.

Moscow officially acknowledges having lost four jets and four helicopters during their intervention in Syria, including two jets that crashed while trying to land on the Admiral Kuznetsov aircraft carrier and a Su-24 bomber that was shot down by Turkey in November 2015.