text: Former Northern Territory politician Matthew Gardiner has reportedly been detained at Darwin airport as he returned from Syria, where he is believed to have been fighting the Islamic State. In January the senior NT Labor party figure fled the country with plans to join Kurdish militants - an action which is penalised with life in prison in Australia. He arrived at Darwin airport early on Sunday morning after flying from the Middle East via Sweden and Singapore, according to . Australian Federal Police confirmed to Daily Mail Australia that a man had been detained at the airport. 'The AFP can confirm that it spoke to a Darwin man today (Sunday 5 April 2015) following his return to Australia,' an AFP spokesperson said. 'Enquiries relating to his activities while overseas are ongoing and as such it is not appropriate to comment further at this time.' Scroll down for video . Former Northern Territory politician Matthew Gardiner has returned to Australia after he was understood to have been fighting ISIS in the Middle East . The 43-year-old, who has an army background, was allowed to leave the country because he was not on any watch list. He left behind his wife Andrea and three young sons, aged between three and 11. They reportedly had no idea of his decision to flee the country before he disappeared. Mr Gardiner is also head of the NT Labor Party, though he was suspended from his role after his disappearance. In February Australian man Ashley Johnston became the first Westerner to be killed fighting against IS for the Kurdish People's Protection Unit (YPG). It's believed the 28-year-old was fighting with the Kurdish People's Protection Unit (YPG) and trying to liberate the ISIS-held town of Tal Hamis in Syria. Johnston was reportedly killed after he became outnumbered when a truck he was travelling in broke down in a small village near Shingal, close to Iraq's border with Syrian Kurdistan. His mother Amanda Johnston had no idea her son was at war in the Middle East until she learnt of his death, as he told her he was simply heading to the Middle East to do humanitarian work. Around 90 Australians are understood to have travelled to the Middle East to join militant causes . Gardiner reportedly headed to Iraq or Syria with the view of joining Kurdish militants and fighting against IS . Mr Gardiner, 43, reportedly served as an Australian Army combat engineer in Somalia in the early 1990s. Attorney General George Brandis was delivered an AFP brief on the Gardiner case. A spokesperson for Mr Brandis said Australians who join militant causes overseas face imprisonment should they survive and return. In January the senior NT Labor party figure fled the country with plans to join Kurdish militants . Gardiner was reportedly detained at Darwin Airport after returning to Australia via Singapore and Sweden . 'If you fight illegally in overseas conflicts, you face up to life in prison upon your return to Australia,' the spokesperson said. 'It is illegal to fight in Syria for either side of the conflict. 'It is illegal to fight for a terrorist organisation anywhere, including in Iraq.' Australians who wanted to oppose the actions of the Islamic State group should instead donate to humanitarian groups operating in affected areas, the spokesperson said. Around 90 Australians are understood to have travelled to the Middle East to join militant causes.
target: Former union official was arrested after returning from the Middle East .
  He left the country in January to illegally join the fight against IS .
  It is understood Matthew Gardiner headed to Iraq or Syria to join Kurdish .
  The Australian Federal Police has confirmed it is investigating the case .
  The 43-year-old was allowed to leave the country because he was not on any watch list, report says .
  A spokesperson for Attorney General George Brandis said: 'If you fight illegally in overseas conflicts, you face up to life in prison'