Desperate family members are urging rioting Waikeria Prison inmates to give themselves up, but warn their loved ones are "willing to die" if their demands for basic needs are not met.
A group of 16 inmates are still evading capture on the jail's roof after starting a riot and lighting fires in the prison yard on Tuesday afternoon.
One woman, who asked not to be named, told the Herald that inmates had been making short phone calls to relatives to update them on the unfolding situation.
She said a family member had taken a call from a cousin inside Waikeria about 10.30pm yesterday.
But her cousin's call is the last time anyone had heard from those inside, she said.
"I haven't slept. Everyone's saying [to them] to give up now."
But they were adamant their calls for basic needs would be heard, she said.
"If there's no change, they're not going back. They're going out in body bags.
"They're willing to die in there."
She called the prison conditions inhumane and said they had been unacceptable for generations of inmates.
"This is the generation to make that stop."
The woman confirmed the men had not been given any food or water by authorities.
In the past day, the protesting prisoners had found a towel and a hose that had been providing them with water to drink. They had also been praying for rain, she said.
The Waikato regional MetService forecast is for showers today with possible thunderstorms and localised downpours, easing this evening.
A MetService spokesperson confirmed a light shower has gone over Waikeria in the past hour or so.
A rain gauge at Bartons corner - midway between Te Awamutu and Otorohanga - recorded 7mm in the four hours leading up to 3pm.
A former Waikeria Prison guard told RNZ the conditions inside the jail are poor and that there is a toxic culture.
The former guard described the water quality as being in an atrocious state.
Six prison vans left the grounds this morning while a number of Fire and Emergency vehicles entered the prison grounds.
Meanwhile, National Party leader Judith Collins has posted on Facebook calling for the Minister of Corrections Kelvin Davis to front up.
"Let's be clear. Mass destruction of taxpayer-funded property, assaulting Corrections staff and hoarding weapons is not a 'peaceful protest'," she wrote.
Davis needed to explain how the loss of control happened and what he was going to do to fix it, she wrote.
"He was perfectly happy to crow about prisons in opposition but now that he's in charge, he's nowhere to be seen."
A spokesman for Davis has said he will not comment or visit the prison until the situation is resolved.
This morning incident controller Jeanette Burns said the 16 prisoners had continued to light significant fires overnight.
"We are absolutely committed to ensuring that this is resolved safely," she said.
"There are multiple risks involved, including the structural integrity of the fire-damaged buildings, the weapons and equipment available to the prisoners, the toxicity of burned building materials, and the violence being offered by the prisoners."
Negotiations with the group are ongoing, she said.
Yesterday Corrections confirmed the rioting inmates had gained access to power tools, tactical equipment including shields and body armour, and built makeshift weapons to use against Corrections staff.
The protesting inmates had also accessed a medical dispensary where controlled drugs are stored and there were now fears for the structural integrity of the badly damaged prison building.