Sixteen prisoners are still holed up in Waikeria prison, where violent protests began on Tuesday.
The men have been holed up in a high-security building since Tuesday, when they lit several fires to protest against poor conditions. The building has since been extensively damaged and the Department of Corrections said it was unlikely to be used again.
The Corrections Department says inmates continued to light fires and cause further damage last night.
One man gave himself up late yesterday afternoon, but was assaulted by the others in an attempt to prevent him leaving.
A Corrections spokesperson said the inmates hurled objects at staff patrolling the area.
Speaking through a lawyer, the prisoners say they are protesting at inhumane conditions at Waikeria and want a peaceful resolution.
Human rights lawyer, Michael Bott, said the inmates described unsanitary and repressive conditions at Waikeria.
"The prison itself, the part that they're in, was built at a different time when punishment was the main goal and it appears that the architectural building of its time has somehow infected the way they are treated today," he said.
Bott said the inmates wanted a peaceful and just resolution but were frightened of the armed police present.
An ambulance was reported to have entered the hospital earlier this afternoon.
A small group of supporters is gathered again today at the perimeter of the prison, which appears quiet today.
Māori Party co-leader Rawiri Waititi visited Waikeria Prison last night to assist with negotiations.
RNZ was yesterday told by whānau of one of the inmates that the prisoners had came down from the rooftop during the evening, and were believed to be in discussions with Waititi.
But an effort by the iwi, Ngāti Maniapoto, to negotiate an end to the prison failed yesterday.
Waititi said he was invited by the prisoners to help with the negotiations.
"I was invited to listen and that's exactly what I did," he said.
"They are clear that this is not a riot, it is a protest for their human rights for all inmates past and present.
"They are protesting for their right to basic human needs. The environment in Waikeria prison is dehumanising. The water they are expected to drink is brown. They don't get clothing or appropriate bedding. They are expected to wash their clothes in the yard shower."
Waititi said the Ombudsman's Report completed in August supported what the prisoners were saying about the conditions.
"When injustice becomes law, defiance becomes duty. These men are at their wits end.
"This situation is indicative of a dysfunctional Justice system that has been failing our people for years."
Waititi is calling on the Corrections Minister to find a resolution to the stand off quickly.
"For a government who prides itself on kindness, they have allowed for an inhumane environment to fester. They are willingly allowing for breaches of basic human rights to occur. They need to sort it out now.
"We need to resolve this immediately for the safety of all involved; for the whānau in prison and for the whānau working in the prison."