Amnesty International has called on the Gillard government to begin the processing of 387 asylum seekers on Nauru immediately after describing conditions at the island detention centre as tougher than those at any of the mainland facilities.
A delegation from the human rights body expressed shock at the conditions at the camp after being given access today, saying the conditions were responsible for a "terrible spiral" of self-harm, hunger strikes and suicide attempts.
"Processing has to start straightaway, or at least tell people when it's going to start and what the time frame is going to be," Amnesty's Graham Thom said at the entrance to the camp after meeting more than 100 of the detainees. "We've heard things like they are dying a death of 1000 cuts.
"All they think is that they have been brought here to be driven crazy, so they will volunteer to go home. That's what they are telling us - and without being able to tell them anything about the processing, how do you dispel those rumours?"
Dr Thom urged the government to have a "close, hard look" at what it was trying to achieve on Nauru, saying the most poignant moments during the visit were meeting people who had harmed themselves or been on hunger strikes.
One of those interviewed was distressed because his brother had been killed last week on the border of Afghanistan and Pakistan.
"In the front of their minds is the fact that they are not being processed and the uncertainty is clearly having an impact on their mental health," Dr Thom said. "We saw people who showed us scars where they have cut themselves. They highlighted a pole where somebody had tried to hang themselves."
Dr Thom and Amnesty refugee campaign co-ordinator Alex Pagliaro returned to the centre to interview more detainees and are planning to visit the hospital where two asylum seekers have been admitted after embarking on prolonged hunger strikes.
Dr Thom described conditions in which up to 14 men were living in a single tent: "In summer, in the heat, it gets to over 40 degrees during the day in those tents and it was certainly very hot and humid when we were in there. When it's raining, as it is now, the tents are leaking and their bedding gets wet at night."
Several of those who met the delegation complained of skin conditions that were a consequence of the humidity and sleeping in wet bedding, a problem that was likely to worsen during the monsoon, Dr Thom said.
"We have very real concerns around their health and their mental health, and we're also very concerned that they were brought here, a lot of them they are claiming by force, to a situation where clearly the conditions were not set up initially and are still not set up to deal with the numbers that are here.
"It's very hard to see people detained in these surreal conditions . . . they are literally in the middle of the jungle, nearly 400 men crammed in tents. It's very hard not to be taken aback by what you see. Their resilience is clearly impressive, but it is quite distressing to see so many in such an extraordinary circumstance."
Dr Thom said the anguish of the asylum seekers was compounded by the question of why they were sent to Nauru.
"The people here don't know why, out of 7000 people who have arrived here post-August 13, they been chosen to come here? Is it a lottery? That is one of the things that's playing on their minds and adding to the distress and the serious concerns that they have."
Although excursions to swim or play volleyball are permitted, Dr Thom said they were inadequate and it was "completely unacceptable'' that many of the asylum seekers were detained 24 hours a day in the hot, humid and cramped conditions.
An Immigration Department official declined to comment on Dr Thom's remarks, saying there would be a response after Amnesty published its report on the visit.