A former Australian soldier, Caner Temel, with basic arms and explosive trainings under Australia, died fighting alongside Syrian rebels. A recruit with such military training is considered an asset for the Syrian rebels as most of the foreigners recruited have no military background.

The Federal Government confirmed through ABC Radio that Mr Temel had served for 17 months in the Army, however, he went AWOL in Sept 2010.

As verified, Mr Temel previously served as a sapper based in Brisbane and Defence has yet to figure out when was the last time he reported on duty.

"He would have done basic employment training (as a combat engineer), basic construction-type work and he was working in a construction squadron at the time," Assistant Defence Minister Stuart Robert told ABC Radio.

"All of our soldiers go through basic arms training. All of our engineers will do a limited amount of explosives work, in terms of clearing obstacles and that type of basic engineering work. Once people leave the military it's very difficult for us to keep tabs on them," Mr Robert explained.

However, Mr Robert admitted that the government was also clueless when and how deep is Mr Temel's involvement with the Syrian rebels.

"We know everything about him while he served with us but as soon as you leave the defence force you are a civilian,'' Mr Robert said.

It was, however, understood that Mr Temel was possibly recruited into the Islamic State of Iraq and the Levant (ISIS), a terrorist group already identified by Australia.

Mr Temel joined a growing list of Australians who were killed fighting with the Syrian rebels.

According to a report from AFP, recruitment of Australians and other foreigners was being headed by a disability pensioner. This pensioner was particularly tasked "for organising travel to Syria for Australian citizens to fight on the front line, including with Jabhat al-Nusra and then with other al-Qa'ida-affiliated groups".

The government, in fact, had already made public about an alarming number of Australians going to Syria to join the war. As estimated, there had been 100 Australians who had been confirmed fighting alongside the Syrian rebels.

The government also believed that there are dozens more Australians fighting with the rebels in Syria. Some might have attained high positions within the extremist Islamic group. The ABC had come up with a list of the Australians who were killed in Syria with alleged associations with rebel groups.

In January, Sydney couple Yusuf Ali and his young wife Amira were killed during fighting with rebels near Aleppo.

In Oct 2013, Roger Abbas, 23, a well-known kickboxer from Melbourne was killed after joining the Jabhat al-Nusra group. He originally went to Syria for volunteer work but was recruited by the group.

Yusuf Toprakkaya, also from Melbourne, was killed by a sniper while he was also fighting with the rebels in Dec 2012.

Mustafa al-Majzoub, a preacher from Sydney, was killed by a rocket. His family said he was in Syria for volunteer work.

In Sept 2013 man from Brisbane was believed to be the first Australian suicide bomber. He blew himself up, killing Syrian soldiers at a checkpoint.

Hamdi Al Qudsi, from Sydney, was arrested for aiding people travelling to Syria to fight with the rebels. He faced seven charges including allegedly helping Yusuf Ali to travel to Syria "with the intent to engage in a hostile activity, in particular engaging in armed hostilities".