AN AUSTRALIAN man has been killed while he was part of an assault on a military base in Syria, rebel groups claimed.
A YouTube video released two days ago from an account connected to Syrian rebels shows a man described as al-Australi (''the Australian''), who was reportedly killed in a battle for control of a main military base.
The video set to sentimental music shows montages of the young bearded man staring defiantly into a camera, carefully mixing explosives and riding on a convoy in military attire.
He is identified only as Abu al-Walid, a name that means ''father of al-Walid'' in Arabic. The video says the man left behind a fiancee to join the fight against the Syrian government.
His identity cannot be confirmed and the Department of Foreign Affairs and Trade says it is unaware of any Australian national having been killed in fighting recently.
But the conflict in Syria and breakdown of its diplomatic relations with Australia has impeded the flow of such information before.
''This would be the first evidence of an Australian who has gone [to Syria] specifically to fight,'' Shandon Harris-Hogan from Monash University's global terrorism research centre said.
He said it was also possible the man could have been a dual national based in Syria.
Estimates from community leaders suggested that between 80 and 300 Australians had returned to Syria since civil war broke out in 2011, overwhelmingly for family or other non-military reasons.
''We've had people killed [before] but we don't know the extent of their involvement,'' Mr Harris-Hogan said.
Conflict in Syria has been raging between forces loyal to President Bashar al-Assad and the Free Syrian Army.
The two groups have been locked in conflict since October for control of the Wadi Deif military base in the country's north-west.
The rebels have beseiged the base and the government has responded by attacking their positions from the air.
If confirmed, the man would be the third Australian to have been killed in the Syrian conflict.
In October a Melbourne man, Roger Abbas, was killed in Syria, after it was claimed he had been caught in crossfire.