MEAA Chief Executive Paul Murphy said Boochani appeared to have been deliberately targeted by Papua New Guinea police in today's crackdown because of his high-profile as a journalist reporting from inside the detention centre.
However, the UN's refugee agency said on Tuesday that housing remained "under construction", was inadequately secured, and lacked "the most basic services" such as a medical care.
"We call on the Australian and PNG governments to release him from custody, assure his safety, and not to hinder him from continuing to perform his role as a journalist".
Their intervention follows several street marches in Australian cities condemning Australia's treatment of asylum seekers on Papua New Guinea. So far, 54 have been resettled while another 500 await assessment of their status.
The Australian camp, which initially housed around 600 refugees, was shut and water and electricity cut off on October 31 after a PNG court ruling. They reportedly managed to persuade 35 of the 378 men to leave for alterative accommodation in the nearby town of Lorengau.
Turnbull dismissed asylum seekers' fears for their safety in Lorengau, accusing them of trying to pressure Australia into resettling them by refusing to move from Manus.
According to the Australian Associated Press, the Governor of Manus Island said locals fear they too will be in danger, so they have armed themselves with knives and other weapons as a precaution.
"We will not be pressured".
Immigration Minister Peter Dutton has told Sky News authorities do not want men to "squat" at the former processing centre.
However, Sudanese refugee Abdul Aziz Adam said it has been the most violent day at the centre since a deadly riot 3 years ago.
He said police are doing the best they can for the refugees but they remain stubborn and defiant and are putting huge pressure on the island's community and its police resources. "I am glad that this relocation exercise was done peacefully and without use of force". This was denied by Australian Federal Police, who said they had no involvement in the operation.
"It's hard to believe the suffering of people seeking asylum could get any worse after five gruelling years of imprisonment in inadequate facilities under unbearable conditions on Manus, where six men have died since 2013".
"Immigration officials went in and explained to them that they really had no legal standing. voluntarily they packed their bags and moved across", he said.
PNG police spokesman Dominic Kakas told the ABC the operation was being conducted by 10 PNG Immigration officials and around 40 police personnel.
"The risks of serious injury if the authorities use force now is completely foreseeable", the London-based rights group's researcher Kate Schuetze said in a statement.
The three were previously arrested and detained in 2015 for peaceful protests at the refugee detention centre. "Shelters, tanks, beds and all of our belongings".
"Immigration and police started searching the rooms and are saying "Move Move" you only have an hour to move", he wrote.