Islamic State Isis fighter with flag
Sharky Jama was among thousands of westerners who have joined IsisStringer/Reuters

An Australian model turned jihadist has reportedly been shot dead in Syria, as Prime Minister Tony Abbot urged his nationals not to fall prey to a "death cult".

The father of Sharky Jama, a 25-year-old of Somali origins, told local radio that he received a call from someone in the war-torn country informing him that his son had been fatally wounded.

"He got a text message and he received a phone call from Syria, someone has told him his son has passed away," SBS Somali radio broadcaster Ibrahim Mohamed said, the Sydney Morning Herald reported.

"Then he said 'I tried his number', because he has contact with his son. Automatically, it goes to voicemail, that's what he said, and then he knew that his son is gone."

Jama worked as a model and DJ in Melbourne before joining the Islamic State (Isis) extremist group. He was reportedly killed in Syria's northern Hasakah province, near the Iraqi border.

After Jama's death was reported, Abbot called on Australians not to join IS a day after his government decided to deploy 300 additional troops to support Iraqi forces fighting against the Sunni extremist group.

"My very simple message to anyone considering joining these groups is - don't. They are death cults. They are not about religion; they are just about death and it is just as likely to be your death as anyone else's," Abbott was quoted as saying by News.com.au.