The youths, aged 16 and 17, were detained by Customs on Friday, after they aroused the suspicions of two Customs and Border Protection officers, Immigration Minister Peter Dutton said. The young Australian alongside two other IS members. Credit:Twitter The teenagers were referred to the Customs Counter Terrorism Unit, which determined that they were intending to travel without the knowledge of their parents. The brothers were allowed to leave the airport with their parents and were issued Court Attendance Notices. On Sunday Prime Minister Tony Abbott said the interception showed the government's tough new foreign fighters laws were working. Meanwhile, Fairfax's investigation can reveal Jake was a high-flying student, a maths whiz, who attended Craigieburn Secondary College's CEAP Excel accelerated learning program. However, he dropped out of high school mid-last year after converting to Islam and bought a one-way ticket to Istanbul, on the way to Iraq and Syria to fight for the so-called caliphate.

In December, Jake's photograph hit Twitter, where a user, Abu Dawud, identified the young man as Briton "Jonathan Edwards". The tweet said he had "applied for Ucas (Britain's Universities and Colleges Admissions Service) to [sic] late and wasn't accepted in any university, so he joined the Islamic state". This undated photo posted on a militant website shows fighters from Islamic State marching in Raqqa, Syria. Credit:AP After Britain's Daily Mail and Daily Telegraph newspapers picked up the story and ran it, Abu Dawud laughed that he had "trolled" and "humiliated" the British media, saying the story was fake, leading to speculation that the picture was doctored. But Fairfax Media has now had the photograph positively identified by friends and also by members of two different north suburban Melbourne mosques as that of a quiet, young Muslim convert who worshipped with them for about a year before disappearing. A photo of 'Jake' during his Melbourne schooling days.

"He used to come here when we had a big lecture," said to Abu Zaid, a committee member of the Hume Islamic Youth Centre in Coolaroo, near Meadow Heights. Abu Zaid said Jake didn't have a car, so he used to ask the other brothers for lifts to and from the centre, which features a prayer hall for more than 1000 people, lecture rooms, a cafe and a gym. The Daily Mail's story on 'Jake' from December 2014. "He was a very quiet guy, he stuck to himself," Abu Zaid said. "We weren't close to him. I didn't see any of the people [getting] close to him." Worshippers at another mosque, the Australian Islamic Social Association in Meadow Heights, also remember young Jake coming there to pray.

It's understood that Jake, who now goes by the Islamic names Abdur Raheem or Abu Abdullah, was 16 when he began feeling unhappy and started searching for spiritual answers. A school friend introduced him to Islam and he recited the Islamic testimony of faith. At the Meadow Heights mosque, people who remembered Jake said his family was negative towards his new religion. A former school friend, who asked to remain anonymous, but said he had known Jake since they were children, said Jake had "made his own choice and he believes its the right choice. "He was notNOT pushed into IS [Islamic State] and was not pushed into Islam. People can make their own decisions and this was one of his ...he felt that it was right for him ... He had done sufficient research to believe it was the right step in life," the friend said. "He was obviously a believer in Islam and wanted to fulfil what he believed was his duties to the religion." Other friends described Jake as extremely shy and quiet, but saidhat he was "really bright". School friend Kutlu Karapinar said he was "quite politically aware for his age". Another, Josh Green-Mercier, said he was interested in different cultures, but "he never seemed very happy".

"I'm not sure why. He usually just listened to us and sometimes talked but rarely. He would just talk about math, etc," Mr Green-Mercier said. A Fairfax Media investigation has revealed that, during his final year of high school in 2014, Jake began communicating via online forums and emails with a supposed American journalist from the BBC. He began telling his family he was going to Istanbul to work with the journalist, even though he had previously expressed little interest in the profession and had no qualifications. It now appears the "journalist" was an Islamic State recruiter. By that stage he had moved to a school in Essendon and was finding the travel difficult from Craigieburn. According to one friend, Jake believed he would fail high school, so he dropped out. A source close to the family says that in August that year, Jake closed down most of his online and social media accounts and disappeared. A subsequent search revealed he bought a one-way ticket to Istanbul. Two months after his disappearance, Jake contacted his family to let them know that he was in Iraq training for a "martyrdom mission" with a suicide vest. Later that month, however, he called again to say he was "too scared to do it and he prefers being a soldier". He proposed to travel to Syria.

Fairfax Media has confirmed with sources in Turkey that at around that time, Jake, using his full Islamic name and his family's surname, was documented crossing into Syria via the Jarabulus or Tal Abyad crossings. The sources also identified him by photographs. Neither the Attorney-General's department nor the Australian Federal Police would comment on the case, but the government says at least 140 Australians have travelled overseas to fight in Iraq and Syria, of which whom at least 20 are known to have died. Jake left little online activity behind, but one is on video-sharing site Livestream, where he followed one user only: the national Muslim organisation Ahlus Sunnah Wal Jamaa Association of Australia (ASWJ). ASWJ is based in Auburn, Sydney, and is associated with the Hume Islamic Youth Centre in Melbourne. It streams lectures via the social media site. Jake's profile picture includes a quote from the 13th-century Islamic theologian Ibn Taymiyyah: "What can my enemies do to me? My paradise is in my heart, it is with me wherever I go. To imprison me is to provide me with seclusion. To send me into exile is to send me away in the Path of Allah. And to kill me is to make me a martyr".