The discovery of the dead man, who was said to be from Iran, was confirmed by David Yapu, a Manus Province police inspector. The police had not released his full identity, citing the continuing investigation.
Inspector Yapu said the body was found at the East Lorengau primary school on Monday morning, close to the East Lorengau Refugee Transit Center.
“He was found hanging; a rope was tied around his neck,” Inspector Yapu said. “He was found by the schoolchildren, who then alerted their teachers, who then alerted police.”
The Kurdish journalist Behrouz Boochani, who fled Iran and has been detained at Manus since 2013, said the man had been struggling with mental health issues for a year.
Mr. Boochani said fellow refugees had petitioned the authorities eight months ago to care for the man but that no action had been taken to ensure his safety.
“They left him most of the time,” Mr. Boochani said. “He was hungry and homeless. Nobody cared about him.”
Mr. Boochani said he had spoken to Australian news outlets several times about the man’s case.
“I feel so powerless. I really tried to help him,” Mr. Boochani said. “I did my best as a journalist. I did my best as a human. I did my best as a friend. I did my best, but he died.”
The rights group Amnesty International said it was “gravely concerned” about how the man had been treated. “This death is yet another bleak tragedy to arise out of the ongoing suffering and tensions on Manus Island,” Graham Thom, refugee coordinator at Amnesty International Australia, said in a statement. “There must be an independent, impartial, prompt and effective investigation into his death.”
According to an April report from the Australian government, 821 asylum seekers are detained on Manus Island.
Mr. Boochani said that medical treatment for the refugees housed on the island was inadequate, with mental illness rife.
“These people are dying here. Why are people dying on this island? Hundreds of people who are there are medically and physically sick,” Mr. Boochani said.
The class-action suit, filed in 2014, sought damages for physical and psychological injuries and for false imprisonment for 1,905 current and former detainees.
The main detention center on Manus Island is slated to close in October, and water and electricity to parts of it have been cut off, but the fate of those still housed there remains unclear.
Detainees have refused to move and staged a protest last week, saying they were being aggressively relocated without any guarantees of protection.
The East Lorengau Refugee Transit Center, near where the body was found, is a separate facility set up to house people who are to be resettled elsewhere, including the United States.
The Obama administration had agreed to accept hundreds of the refugees from Manus and Nauru, and while President Trump has questioned that decision, Australia has said that the United States would honor the deal. It was not clear whether the man whose body was found was among those eligible to be resettled.
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