A tense stand-off between Waikeria Prison inmates and the authorities is heading into its third day.
Prisoners have been rioting since Tuesday afternoon, and 17 prisoners remain non-compliant.
The damage the prisoners have caused to Waikeria Prison is extensive - a third of its bed capacity has been destroyed.
Rioting prisoners lit fires in an exercise yard before climbing onto the roof on Tuesday where they were continuing to cause mayhem yesterday.
Corrections Communications said just after 7am today that there had been no change to the situation overnight.
A police spokesman said their officers remain on the ground early this morning as well.
"Police are still in attendance supporting them," the spokesman said.
The riot is the biggest in a New Zealand prison since 2013, when more than 20 prisoners went on a nine-hour rampage at Springhill Prison.
Department of Corrections staff had not supplied them any food since the rioting started and were attempting to negotiate with the prisoners.
It is not known why the prisoners started rioting but the reason could be an alleged lack of access to phones, Corrections chief executive Jeremy Lightfoot said.
The department was not aware prisoners were about to riot until after they were contacted by media about midday on Tuesday.
Checks immediately afterwards found nothing. But when prisoners were in the yard that afternoon they started lighting fires.
About 20 prisoners were thought to be in the yard at the time but not all were involved in the riot.
On Tuesday night, some of the prisoners from the yard and others who broke out of their cells made their way to the roof where they set alight mattresses.
The prisoners also allegedly took toilet doors off their hinges and used them as weapons against Corrections staff.
Specialist Advanced Control and Restraint teams, made up of staff from a range of prisons, have been at the jail since early Tuesday afternoon.
Prison Corrections Association union representative Alan Whitley said guards work in "horrible" conditions where the rioting is taking place.
He said the section of the facility is well past its use-by date.
Damage to the area has been "significant" and it's likely prisoners will never be able to be accommodated there again, Lightfoot said.
The prison has lost roughly a third of the prison's capacity - 250 beds - as a result of the fire damage.
At the height of the fires, 75 Fire and Emergency crew were at the prison but by mid-afternoon yesterday only 45 were there.
There were concerns about smoke inhalation for prison staff but no one was treated for any injuries, Lightfoot said.
The rioting inmates smiled and waved at cameras as they set fire to two cell blocks and smashed cells with makeshift weapons.
Three Corrections officers and two prisoners were injured and about 100 inmates had to be relocated to other prisons around the country.
Corrections had removed at least 49 prisoners from one unit in Waikeria since the rioting started.
The most important stage of the riot response was removing prisoners not involved and staff safely away, Lightfoot said.
However, he would not be sending staff into the unsafe environment to finish the stand-off, saying "we must be focused on the threat to life".
Police negotiators are working alongside Corrections but Lightfoot would not go into details about how they were communicating with the prisoners.
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