Sydney - Asylum seekers kept at an Australian-run detention centre in Papua New Guinea's Manus Island will never be allowed into Australia, despite recent protests, the government told reporters on Friday.New Immigration Minister Peter Dutton said there had been no weakening of the Australian government's resolve since he took over from Scott Morrison in December.Dutton said he was worried about the "volatile" situation at Manus Island where asylum seekers are reported to have sewn their lips together and swallowed razor blades and washing powder as part of a protest that began on Tuesday, broadcaster ABC and The Guardian Australia reported.Around 500 of the 1 030 asylum seekers being kept in the camp are reported to be on a hunger strike. Guardian Australia reported several men have collapsed saying they didn't care if they died. Dutton confirmed there had been acts of self-harm at the camp and one detainee was being treated outside the camp.Dutton said people outside the camp had been encouraging the behaviour by telling the detainees it could help them get to Australia."My message today is very clear to the transferees on Manus and in other facilities: whilst there has been a change of minister the absolute resolve of me as the new minister and of the government is to make sure that for those transferees they will never arrive in Australia," Dutton said.The government says those deemed to be refugees can settle in PNG or Cambodia. Some detainees have reportedly said they fear for their safety if placed in the PNG community.Meanwhile an Iranian asylum seeker who has been on a long hunger strike in Darwin was sent back to the detention centre after he was treated in hospital.The 33-year-old man has spent four years in detention and stopped eating two months ago after he was refused a visa.