The mother of Ashley Johnston has revealed how she did not know her son was fighting against ISIS until he was killed in Iraq. The former Australian soldier was reportedly fighting for the Kurdish People's Protection Units (YPG) in Iraq and Syria but was killed on February 24. The truck he was travelling in reportedly broke down and his group were 'outnumbered and outgunned' by ISIS fighters. A fellow fighter also recalled how Johnston died, saying the Australian 'sacrificed himself' for his comrades. This comes as Johnston said in his final interview before his death, that he was afraid of returning home because he thought he'd be treated like a terrorist. Scroll down for video . A former Australian soldier was reportedly fighting for the Kurdish People's Protection Units (YPG) in Iraq and Syria but was killed on February 24 . The Lions of Rojava, a band of volunteers that help recruit soldiers to the YPG, claimed Ashley Johnston was 'outnumbered and outgunned' The Australian reportedly died on February 24 in a small village near Shingal in Iraq, close to the border with Syrian Kurdistan . Amanda Johnston, of Canberra, told The Sydney Morning Herald that she thought her son was with the Kurds because he was doing some humanitarian work. Ms Johnston said she only knew of his whereabouts from a text message sent by her son on December 30. Johnston had informed his mother that he was in the Middle East 'supporting the Kurdish people'. Ms Johnston learnt of her son's death on Thursday, saying she was shocked by the news and is in disbelief that he was killed while fighting ISIS. 'I just kept calling because I didn't believe it was true. I know in my head that it is actually Ash but the rest of me doesn't like to believe it's true,' she said. 'I just said, "I need to talk to you. You have to ring me. I don't believe that what I've been told is true. I need you to ring me and tell me what's going on … I need to hear your voice."' It is believed the 28-year-old's remains are in an unstable area near the Iraq and Syria border. However measures are being taken by the Department of Foreign Affairs and Trade in order to bring his body back home, The Sydney Morning Herald reports. The Lions of Rojava posted this tribute to the Australian man they claim has been killed while fighting for them . It is believed the 28-year-old's remains are in an unstable area near the Iraq and Syria border . Measures are being taken by the Department of Foreign Affairs and Trade in order to bring Mr Johnston's body back home . Ashley Johnston told Vanity Fair reporter James Harking he was afraid of a lengthy prison sentence back in Australia. The 28-year-old, from Queensland, served for seven years with Australia's Army Reserves before going travelling and becoming moved by struggle of ethnic Kurds against ISIS militants who have taken control of large parts of Syria of Iraq. He fought in Iraq and Syria with the Kurdish People's Protection Unit, known by the acronym YPG, under the name Heval Bagok Serhed and was reportedly killed on February 24 in a small village near Shingal in Iraq, close to the border with Syrian Kurdistan. Fellow comrades say Johnston died after a military tank was encircled by ISIS fighters, so the Australian sacrificed himself as he 'jumped out of the panzer to cover us' A fellow fighter detailed one of the final conversations she had with Johnston, who said that he fought for the Kurdish People's Protection Units (YPG) because he 'couldn't take the children and women that ISIS-thugs slaughtered' The Lions Of Rojava said in a statement: 'What we can disclose is his story of heroism and self-sacrifice for the Kurdish people. Throughout his time in Kurdistan he had a positive impact on my people's lives though his humility and kindness to everyone he met. 'He was taken from us in a heroic assault on ISIS positions in a small village near Shingal. His squad of eight fighters were in a truck which had broken down and it was critical that they dislodge ISIS from their positions so they pushed on fearlessly with little regard for their own safety. 'They were massively outnumbered and outgunned but fearless in the face of this as they knew another ISIS death meant saving the lives of countless civilians. He was a fearless and exceptional soldier as well a great man,' the Facebook statement read. Days later, a fellow fighter Bejan Dagli a YPJ fighter, told of her final moments spent with Johnston on the same Facebook page. When she asked the former Australian soldier why he was fighting for YPG he said: 'ISIS is a world's problem. I couldn't take the children and women that ISIS-thugs did slaughtered and that's why l have come to Kurdistan.' Dagli says other comrades who witnessed Johnston's death said that 'he sacrificed himself for us'. When asked how, one of the comrades responded with tears in her eyes: 'The panzer that we were inside was encircled by the ISIS-thugs and he jumped out of the panzer to cover us that we could break the encirclement and then he got martyred while trying to cover us and break the siege.' Dagli also released photos she had taken of Johnston just five days before his death and wrote about how he was picking up Kurdish. Ashley Johnston (front, second from right) has been remembered by his friends as the 'best mate' Fighter Bejan Dagli wrote about the final moments of former Australian soldier Ashley Johnston . This comes after the YPG shared the grotesque images and celebratory message on their 'Lions of Rojava' Facebook page, claiming that the murders by YPG and YPJ were in the name of Ashley Johnston, his family and for Australia. 'The YPG & YPJ has killed many ISIS terrorists pigs in Til Hemis,' they wrote. 'Our Comrade from Australia, Heval Bagok Serhed, was martyred during the liberation of Til Hemis.' They gloated that the slaughter was a form of payback for Johnston, who they refer to as a 'martyr'. In the images soldiers hug, smile and pose with the peace symbol. 'We took revenge for Heval Bagok, for his family, Australia and the world. His comrades says that it was a revenge for him and his family.' Ashley Johnston, 28, originally from Maryborough, Queensland but had most recently been living in Canberra, was remembered by friends and colleagues from an Australian army rifle brigade as 'a good man' and 'the best mate'. It is understood that Johnston is the first foreign casualty from the Kurdish People's Protection Unit (YPG). 'Defence is aware that a former Australian Army Reserve member is believed to have been killed in northern Iraq while allegedly fighting with Peshmerga forces against Daesh,' the ADF said in a statement. 'Due to the provisions of the Privacy Act, Defence will not release further information about the former member's military service or their personal details.'
Australian Ashley Johnston was killed in Iraq while fighting ISIS . He was fighting for the Kurdish People's Protection Units (YPG)
His mother didn't know her son was fighting ISIS until he was killed . Amanda Johnston thought he was doing humanitarian work with the Kurds . Kurds say Johnston 'sacrificed himself' when tank was encircled by ISIS . 'He jumped out of the panzer to cover us', a fellow fighter said .