A screenshot from a video of the incident obtained by Fairfax Media. "His outlook is not good at all. I send our best wishes and condolences in the circumstances to his wife as I understand it, to family." The video shows a highly agitated man yelling, before setting himself alight. Bystanders scream in horror and rush in to douse the flames with water and blankets. The victim's clothes appears to be burnt off during the incident, after which he lies face down on the ground, apparently suffering severe injuries. A separate video has also emerged that appears to show the man being treated in hospital after the incident. The victim is standing beside a hospital bed and at first seems calm, but then begins screaming uncontrollably.

The camera pans to a nurse who appears distressed at the scene before her, and is vomiting into a bucket. The Nauru government said the man was in a critical condition and counselling had been offered to witnesses, service providers and the man's friends and family. It is understood the man's first name is Omid. A friend of the family who identified himself as Arman told Fairfax Media on Wednesday afternoon that Omid's wife was distraught after witnessing the incident, which he said came without warning. "She saw everything. She was screaming and she wanted everyone to put the fire out," Arman said. He feared Omid was now "really dying" and questioned the delay in airlifting him to Australia.

Asked why he believed Omid set himself alight, Arman said "we are in hell. Nauru is like a burning hell - all of us are suffering here." A source at Nauru said the man, who lived in the community at the Nibok settlement, poured a 20-litre bottle of petrol over himself and cried "this is how tired we are, this action will prove how exhausted we are. I cannot take it anymore." The source said the man spoke to UNHCR representatives of "the intolerable mental and physical pressure on refugees and particularly on himself, who [is] imprisoned at Nauru." UNHCR regional representative Thomas Albrecht said his organisation was concerned about the "grave mental state of asylum seekers and refugees" and urgent action was needed to prevent further suffering and address worsening mental health. The UNHCR had been in Nauru since Sunday conducting a monitoring mission of arrangements for asylum seekers and refugees transferred from Australia.

A refugee advocate who is in close contact with those at Nauru said tensions were high after the Papua New Guinea Supreme Court on Tuesday ruled the Manus Island detention centre was illegal, opening up the prospect that detainees there could be released. "People are thinking 'what about us'. They are feeling desperate," the advocate said, adding she believed the man had burns to 80 per cent of his body. The incident follows a Nauruan court decision in February to convict and fine a refugee for attempted suicide in a move authorities said was designed to "stamp out the practice". In a statement the Nauru government said incidents such as that on Wednesday morning were an attempt to "influence the Australian government's offshore processing policies". "Emergency services and medical personnel responded quickly and the person is being treated in hospital for serious burns. Nauru's new hospital is now open and the patient is receiving excellent medical care, while medical evacuation to Australia is currently being considered," it said.

The Nauruan government urged refugees "to refrain from such protests for the protection of themselves and others". "Nauru has invested considerable time and money into services to assist the refugee community socially, emotionally, medically and vocationally, and to ensure all refugees are safe in our country. There is no value in such behaviour," it said. Greens immigration spokeswoman Senator Sarah Hanson-Young said the situation at Nauru "requires immediate, emergency intervention". "The Immigration Minister must explain exactly what is happening on Nauru and explain what the government will do to get out of offshore detention before more lives are lost," she said. With Michael Gordon and Bianca Hall

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