The rioting prisoners at Waikeria Prison are starting to fashion makeshift weapons and body armour out of material they're finding on the jail's roof, according to the Department of Corrections.
They're also believed to be in possession of drugs after raiding medicine stocks at the prison.
There are fears the days-long standoff will end with a violent confrontation after several of the inmates assaulted one of their own.
Corrections said on Friday that a prisoner who surrendered to staff on Thursday was "assaulted by the others" before leaving the facility and that other protesting inmates "attempted to prevent him from leaving".
There are 16 prisoners still not complying with authorities at the prison, which has been left with significant damage after inmates lit several fires.
"The prisoners have continued to cause extensive damage to the facility, including forcibly accessing restricted areas including a room used to store tactical equipment that includes power tools, shields, batons and body armour," said Corrections incident controller Jeanette Burns.
"They have also constructed a number of makeshift weapons that we believe they are planning to use against staff, and accessed a medical dispensary where controlled drugs are stored.
"While the group state that they are protesting conditions at the prison and not rioting, their actions are clearly violent."
When Māori Party co-leader Rawiri Waititi arrived at the prison to negotiate with the rioters on Thursday night, he had his own backup - three supporters all the way from Te Puke who's whanau are among those on the roof protesting.
One of them was Gunnyo, who told Newshub the prisoners are treated poorly.
"They don't get towels for three weeks, five months they wait for clean bedding - three weeks for clean clothes. Corrections doesn't listen," she said.
Waititi wants the situation to be resolved peacefully.
"I don't want anybody hurt. We don't want any deaths, ultimately," he said.
The politician's presence had been requested by the prisoners.
"The problem is the prisoners won't listen to anybody of authority at this particular time," said Waititi.
"So we've gotta just look at how many other ways we can do this to ensure that we come to an amicable outcome."
But despite his visit, more fires were lit at the prison last night.
Now the Opposition is speaking up on the riot.
"[Minister of Corrections] Kelvin Davis needs to front up and he needs to head down to Waikeria prison and talk to the staff," National Party Corrections spokesperson Simeon Brown told Newshub.
"[He needs to] show his support and ensure that Corrections and all of the first responders - the emergency responders who are on the scene - have all of the resources that they need so they can bring law and order back to the situation at Waikeria prison as soon as possible."
But Davis said there's no chance he'll visit the prison until the prisoners come down and the issue is resolved.
The inmates claim that won't happen until their complaints about the conditions are addressed.
Gunnyo said the disorder is not a riot, but a protest.
But Corrections said the 16 remaining prisoners involved overnight "caused further damage, throwing objects at guards patrolling the area".
"Yesterday the prisoners agreed with negotiators to surrender if they were able to speak with kaumatua. This was facilitated however did not resolve the situation," said Burns.
"Later in the day the prisoners committed to surrendering if they could speak with MP Rawiri Waititi. This was also facilitated and did not resolve the situation. We have negotiated in good faith, and prisoners have defaulted on the commitments that they have made."
Corrections is demanding the prisoners surrender - at which time they will be given water and further access to kaumatua.
However, with weapons reportedly being constructed by the men involved, there is serious concern that there will be more violence before the incident is resolved.
