The official command of the Kurdish People's Protection Movement (YPG) have paid tribute to a 28-year-old Queenslander killed last week fighting with its forces in west Kurdistan. Former army reservist Ashley Johnston is believed to have been killed on 23 February during an assault by Kurdish forces on an Islamic State (ISIS) position at Gassan, near Til Hemis in Rojava, a Syrian Kurdish region near the Turkish border. Johnston, who adopted the Kurdish nom-de-guerre Heval Bagok, is understood to be the first Westerner to die fighting with the array of militia groups opposed to Isis. "We have been honoured of [sic] Ashley's participation with our humble defence forces, which is build [sic] on our own intrinsic desire for freedom," the statement, released on the Twitter account of the YPG's official spokesman, said. "Ash was not only a fighter providing additional forces to our struggle. In fact, with his experience and knowledge he has been an example for younger fighters. "On [sic] the dark hours of February 23, 2015, where he exercised immense belief and strength in the very frontline, we lost Ashley. On the fearless march toward the post of the terrorist, he lost his life to a cowardly fired bullet." The tribute revealed that Johnston, who served seven years in the Australian army reserve as a combat medic and rifleman, joined the Kurdish militia on 4 January last year. Messages posted on Kurdish social media on Friday claimed that Johnston died after Isis fighters surrounded a tank he was riding in with his squad. "Bagok jumped out of the panzer to cover us [so] that we could break the encirclement and then he got martyred while trying to cover us and break the siege," it was claimed. Images were also posted online last week by Kurdish fighters showing rows of bodies, which they said were Isis fighters killed in revenge for Johnston's death. Flowers were also left outside the Australian embassy in Washington DC by American Kurdish supporters. YPG is not listed as a terrorist organisation in Australia, although it is believed to have links to the Kurdistan Workers party (PKK), a proscribed organisation. Fighting with any non-state group in Syria was banned by security legislation passed last year, and Johnston could have faced at least 10 years in jail in Australia for his role. At least 90 Australians are fighting in the region with Isis and other non-state militia, and at least 20 have been confirmed to have died. A 43-year-old Northern Territory Labor party official, Matthew Gardiner, is believed to have joined Kurdish forces in January. According to Kurdish media reports the town of Til Hemis, which served as Isis's headquarters in the Rojava region, was "fully liberated" on Friday. Kurdish forces were supported by international coalition air strikes, the reports said.