A fighter jet is engulfed in flames in this still picture taken from amateur video said to be shot on August 13, 2012. The video showed a fighter jet engulfed in flames in the sky in an episode described in the video as rebels shooting down a Syrian army fighter jet over the town of Mohassen, in Deir al-Zor province in Syria. [Photo/Agencies]

ALEPPO, Syria - Syria's rebels were jubilant on Tuesday, claiming to have shot down a jet and captured its pilot.

Video uploaded onto the Internet on Monday showed the jet bursting into flames as it streaked through the sky amid heavy gunfire. The rebels said they had hit it with newly acquired high-calibre anti-aircraft guns.

The government said it had crashed due to technical problems while on a "regular training mission".

Rebels also released a video of a man they said was the pilot. They said he had been captured after ejecting while his stricken aircraft plunged from the sky.

"We will treat this prisoner according to what is required of us by our religion, our morals and the protocols in the Geneva convention related to prisoners of war," a rebel identified as Captain Abu Laith said in the video.

However, other disturbing footage on YouTube appeared to show rebels meting out violent justice. In one video, dead bodies are thrown from the rooftop of a post office, while a crowd of shouting men watch. Enraged members of the crowd kick the bodies down stairs and can be heard calling them members of the shabbiha pro-government militia.

In another video, a young man's throat is slit with a knife by captors who accuse him of being a member of the shabbiha while his blood pours on the ground and his last breath rattles. Rebels said the video may have been made by government forces to discredit them.

The downing of a fighter jet would be a rare coup for the lightly armed rebels up against the superior weaponry of Assad's forces, which have made increasing use of air power in recent months.

The Pentagon said it deplored what it saw as Assad's increasing use of air power but stopped short of suggesting any move towards steps such as a no-fly zone.

Reuters journalists have seen fighter jets firing rockets at rebel-held villages and districts in the northern city of Aleppo, Syria's biggest city and this month's main battle front.