Watch: Amateur video shows Syrian rebels purportedly shooting down military jet

Syrian army say investigating cause of military plane that crashed in southern part of embattled country.

Syrian military jet shot down
Syrian rebels said they had shot down a military jet on Thursday in southern Syria, where insurgents fighting to topple President Bashar Assad seized a major army base earlier this week.
Bashar al-Zoubi, leader of the Yarmouk Army rebel group, said his fighters had shot down the Russian-built MiG using anti-aircraft guns.
Videos posted online by the opposition affiliated Syrian Media Organization appeared to show a jet falling from the sky, smoke billowing from the ground after impact, and armed men standing by a burning wreckage.
Syrian officials could not immediately be reached for comment.
An insurgent alliance including rebels backed by Assad's Arab enemies captured the military base "Liwa 52" on Tuesday. The Syrian military has not commented on the loss of the base.
It has compounded losses for Assad since March in the south, the east and the northwest where he has lost territory to an array of insurgent groups including the al-Qaida-linked Nusra Front and Islamic State.