ABOUT 200 Australians are fighting in the Iraq-Syria war zone, a figure more than 20 per cent higher than that reported by Australian authorities, according to a visiting regional expert citing security sources. 
There are an estimated 140 Australians fighting with Islamic State and al-Nusra Front terrorists and another 60 fighting with opposition forces, including Kurdish militia, academic and publisher Kerim Balci said during a briefing in Melbourne.
Mr Balci said Australian and other Western recruits were paying as little as $20 to smugglers to cross the Turkey-Syrian border and up to $200 to get into Iraq to join the conflict.
The numbers referred to by Mr Balci - which may include those awaiting entry to Iraq or Syria - were significantly higher than that cited by Australian Security Intelligence Organisation director-general Duncan Lewis early last month.
Mr Lewis said while almost 200 Australians within Australia were actively supporting IS, ASIO believed 110 were on the ground fighting with all militant groups combined in Iraq and Syria and up to 51 Australians had been killed on the front lines.
The number of casualties include another two Australians believed to have died in recent weeks and an Australian source said ASIO was confident in the numbers it assessed as still fighting in the region.Mr Balci, editor-in-chief of the Turkish Review Journal, said more needed to be done to combat IS's narrative and ideology in digital media.