An Australian politician who reportedly escaped the country to join the war in Syria would have been assisted by new friends he made online, terrorism experts believe.
Matthew Gardiner, 43, disappeared from his Northern Territory home several weeks ago, leaving behind his wife and three young sons.
He was stood down as the president of the Northern Territory branch of the Labor Party and had his membership suspended on Sunday following shock reports that he may have joined Kurdish forces fighting against Islamic State in northern Syria.
The Australian Federal Police confirmed they were investigating Mr Gardiner's movements.
The union organiser claimed to have 10 years' experience in the army, including service in overseas conflicts, and he campaigned for better rights for public service workers, refugees and Aboriginals.
"I served as a soldier for many years to uphold this country's ideals and these racist rants aren't those ideals," he posted in 2011 following calls from shock jocks for defence members to fire warning shots at unruly detainees at a Darwin immigration detention centre.
However, among his thousands of social media posts, there was not a single mention of overseas conflicts or Islamic State.
His last post on social media on December 16 was a plea following the Sydney siege: "Don't give in to hate #illridewithyou."
Mr Gardiner was more concerned with heckling the state's Liberal MP Natasha Griggs and posting happy snaps of his sons, aged between three and 11.
He posted recently about teaching his son to ride a bike and making breakfast in bed for his wife, real estate agent and slow-food campaigner Andrea Gardiner.
Monash University terrorism expert Greg Barton said it was an unusual case because of the man's age but, like most other foreign fighters, Mr Gardiner would have been led to make the decisions based on new friendships.
In the lead up to his disappearance, he reportedly "defriended" most of his Facebook friends and became friends with a person who constantly posted about the Kurdish oppression.
"It's clear he had a romantic desire to help the less fortunate and was motivated by wanting to make a difference," he said.
"In the grips of new friendships those underlying tendencies to speak up for the little guy and champion the weak can go off in new directions very quickly."
Mr Gardiner faces a lengthy prison term if he returns to Australia because it is illegal to fight on either side of the Syrian conflict.
On Monday, federal Opposition Leader Bill Shorten said Mr Gardiner "obviously feels very strongly about fighting ISIL but I don't think it's the right way to go about it, just to up sticks."
"I think he's made a mistake," he told Fairfax Radio.
Mahmut Kahraman from the Australian Kurdish Association said he was shocked that someone with little connection to Kurdistan would take up arms.
He said there was a sudden surge in interest for the Kurdish cause when fighting broke out in Kobane last year.
"Until recently, Australia didn't have much support for the Kurds," he said.
Mr Gardiner was also the treasurer of the peak body Unions NT and the secretary of hospitality, childcare and emergency services union United Voice in the Northern Territory.
He resigned as the secretary of the United Voice union just before he disappeared.
Mr Gardiner was born in Sydney and appeared to be an avid supporter of Parramatta and the NSW Blues in rugby league.