West Papuan independence campaigners have called for the release of an activist who has been put on trial for treason after he helped gather signatures for a petition. Yanto Awerkion was arrested for his involvement in a pro-independence petition which gathered more than 1.8m West Papuan signatures. The petition, calling for a free vote on independence, had been outlawed by Indonesian authorities but was smuggled out of the region and delivered to the United Nations in September. The 27-year-old man is deputy chair of the Timika branch of the pro-independence West Papua National Committee (KNPB). According to his supporters he was arrested after getting on stage to speak about the petition at an event in May. Melanesian leaders condemn UN for turning 'a deaf ear' to West Papua atrocities Read more The Free West Papua campaign said Awerkion's health had seriously deteriorated in jail, and he had not been able to see his wife and daughter. If convicted on the charges relating to sedition and separatism, conspiracy and incitement to commit an offence, Awerkion could face a prison term of between six years and life. His trial was scheduled to begin in Timika on Tuesday. In a video filmed from prison for the Free West Papua movement, Awerkion described himself as a political prisoner. "Because of struggling for Free West Papua, I was arrested by the Indonesian military and police, and I remain in prison," he said. He called for international diplomats to "unite and urge the world and the United Nations to intervene in West Papua and to immediately organise a referendum in West Papua". A spokesman for the Indonesian embassy in Australia, Sade Bimantara, said the rights of people to "peacefully voice their opinions" were protected under Indonesian law, but "when laws are broken, the authorities will act to enforce the law". This included activities supporting or inciting acts that aim to "take over or separate a part of the Indonesian territory and the formation of a new state in its place", he told Guardian Australia. West Papuan women left isolated and beset by violence under Indonesian rule Rochelle Jones Read more Bimantara did not detail Awerkion's alleged actions, but said "separatist groups in Papua and West Papua have been found to commit a number of offences", and noted the death of a policeman last year. Awerkion is not believed to be facing charges involving violence. Bimantara said that was a matter for the prosecutor. The petition asked the UN to "put West Papua back on the decolonisation committee agenda and ensure their right to self?determination ... is respected by holding an internationally supervised vote". West Papua was annexed by Indonesia in 1963, an act formalised six years later with a widely discredited UN-supervised vote known as the Act of Free Choice. The only voters were 1,063 people selected by the military and compelled to vote in favour of Indonesian annexation. "In the West Papuan people's petition we hand over the bones of the people of West Papua to the United Nations and the world," exiled independence leader Benny Wenda told the UN when the petition was handed over. "After decades of suffering, decades of genocide, decades of occupation, we open up the voice of the West Papuan people which lives inside this petition. My people want to be free." Indonesian foreign ministry spokesperson Arrmanatha Nasir said at the time the petition was "purely a publicity stunt with no credibility". The petition also called for the appointment of a special representative to investigate human rights abuses but was ultimately rebuffed by the UN's decolonisation committee because West Papua was outside its mandate. There are frequent reports of mass arrests and violence by Indonesian police and military forces against separatists and their supporters, but information is difficult to verify because of restrictions on foreign media entering the territory. The leader of the Greens, Richard Di Natale, called for the Australian government to make entreaties on behalf of Awerkion and other prisoners, and to support West Papua's calls for a UN-backed referendum.