The death of a Rohingyan refugee who was in Australia’s care on Manus Island is another preventable tragedy that is a direct result of the bipartisan policy of cruelty, Greens Immigration Senator Nick McKim says.

“This man sought Australia’s help, and suffered years of deprivation for daring to ask,” Senator McKim said.

“His death is a direct result of political decisions of the Labor and Liberal parties.”

“He faced the impossible choice of indefinite detention, or returning to face ethnic cleansing in Myanmar.”

The death of a sixth man on Manus Island is another indictment on the Labor and Liberal policy of deliberately harming people on Manus and Nauru, Greens Immigration spokesperson Nick McKim says.

“This is a case of catastrophic neglect by Peter Dutton,” Senator McKim said.

“The policy of deliberately harming people seeking asylum– which is shared by the Labor and Liberal parties - appears to have taken yet another life.”

“This man had suffered for years in a system that Australia’s Labor and Liberal parties deliberately designed and operated to cause mental harm.”

An independent autopsy is needed into the death of of Hamed Shamshiripour on Manus Island, Greens Immigration spokesperson Nick McKim says.

"It's important that people, including Hamed's fellow detainees, have confidence in the autopsy's findings," Senator McKim said.

"Hamed was Australia's prisoner, and it is the Australian government's responsibility to determine exactly how he died."

"Unfortunately, Hamed's death has shown how volatile and desperate the situation is in Australia's offshore detention centres."

The death of a man on Manus Island represents an abhorrent failure by Peter Dutton and Malcolm Turnbull, Greens Immigration spokesperson Nick McKim says.

"This death can be laid squarely at the feet of the man who should have looked after him - Peter Dutton," Senator McKim said.

"This man repeatedly sought Australia's help. The Liberals ignored his pleas and now must bear responsibility for what happened."