Sydney, June 17 (IANS): An Australian teenager feared to have joined a terrorist organisation in Syria has written on Facebook that he is doing humanitarian work there.

Oliver Bridgeman, 18, left his home in Australia's Queensland state in March saying he was going to do aid work in Indonesia, but was later found to be in Syria, reported Xinhua news agency.

Rumoured to have joined the Al Nusra Front, the official Syrian affiliate of al-Qaida, his parents insisted he had not joined the conflict or taken up arms for a terrorist group after leaving Australia.

"I am not associated or fighting for any terrorist organisation or rebel group inside or outside Syria," Bridgeman wrote on Facebook.

"My only activity in Syria is distribution of medical supplies, food and basic life essentials inside the rural parts and Turkish boarders of Syria," Bridgeman added, saying that he was working in parts of Syria which were free from fighting.

About 100 Australians are estimated to be in the conflict zones in Syria and Iraq.