AMMAN (Reuters) - The Syrian military said on Tuesday that one of its jets crashed in southern Syria, state television reported, hours after Western-backed rebels said they had shot it down and captured the pilot.

State-owned Ikhbariya television quoted a Syrian army source as saying an investigation was under way to determine what caused the crash. It did not mention the fate of the pilot.

Rebels released photos of a pilot they identified as Major Ali al Hilwa, with bruises on his face, and the wreckage of a jet they said was a Russian-built MiG brought down by anti-aircraft guns.

Saad al Haj, spokesman for the Osoud al Sharqiya rebel group, earlier told Reuters the rebels shot down the jet in the eastern countryside of Sweida province in southern Syria near the border with Jordan.

“The pilot is being treated for wounds and we are interrogating him,” said Younis al-Salameh, another official from Osoud al Sharqiya, one of two major rebel groups operating in the area.

The eastern part of Sweida province borders Jordan in a front where the Syrian army, alongside Iranian-backed militias, had established control last Thursday over checkpoints and border posts.

Mainly Western-backed Free Syrian Army (FSA) rebel groups still control much of Syria’s southwestern frontier with Jordan and Israel.

Sweida province was not included in a U.S.-Russian brokered ceasefire that took effect in nearby areas of the southwest in July.

Free Syrian Army rebels who get support from a command room in Jordan run by Arab and Western backers of the insurgency say the plane was downed during heavy fighting in the area where they were trying to regain lost ground.

They blamed recent losses on the sudden retreat by a Jordanian-backed tribal militia known as Jaish al Ashair that had patrolled the border area.

This had allowed the army to quickly overrun the border posts and establish a presence in a border strip abandoned in the early years of the conflict.

Jordan has expressed concern about the presence near its border of Iranian-backed militias whose role has been crucial in recent gains by the army in the south eastern Syrian desert known as Badiya.

Last June Osoud al Sharqiya said a military jet had come down about 50 kms east of Damascus in a rebel-held territory near a frontline with army troops.