Two more prisoners have pleaded guilty to charges due to their involvement in the country’s largest-ever prison riot, as 12 others prepare to go to trial.

Both men, who have name suppression, appeared separately in the High Court at Hamilton today when they each pleaded guilty to representative charges of being a member of a riot, unlawfully damaged property, reckless damage of property by fire knowing that danger to life was likely to ensue and assaulting various individuals with various objects or weapons.

An agreed summary of facts revealed it was a dispute over razor blades that ultimately led to 17 prisoners setting fire to wooden structures, throwing cups of urine at Corrections staff, and threatening to assault them between December 29, 2020, and January 3, 2021.

The court document also states that at least $50 million worth of damage was caused by the fires.

However, one of those who pleaded guilty today, represented by Ron Mansfield KC, said although he admitted his part, he disputed the crown’s estimated cost of the damage.

That specific line was taken out of the prisoner’s document and the issue would be sorted at sentencing, which was tentatively set down for March.

Meanwhile, 12 accused are set to go on trial for their alleged actions in the riot later this month.

The summary of facts states on the morning of December 29 there was an incident in the exercise yard after disposable razors would not be handed over to Corrections staff.

A principal corrections officer advised a prisoner they would all be returned to their cells early if the razors were not surrendered, the group said that they were not going anywhere and were ready to fight.

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Eventually, one razor was handed in and the situation was de-escalated, with the prisoners allowed to continue to stay outside until 2pm as was routine.

However, at midday, another co-defendant contacted news media and announced their collective effort to riot against prison conditions.

Subsequently, the nine defendants in the exercise yard set fire to wooden structures and seats, covered security cameras with toilet paper, prevented Corrections staff from extinguishing the fires, threw cups of urine at them, and threatened to assault them if they attempted to enter.

A second phone call was made to the same news media outlet at 2.19pm, stating that they intended to “go to war”.

After that call, a prisoner escaped the yard by climbing on to the roof.

Nine others followed and prisoners housed in the upper levels were freed by defendants using an iron bar to smash through cell windows.

Twelve were freed and eight of those chose to join the riot, while the remaining prisoners were evacuated.

Over the next three days, from December 30 to January 1, the defendants continued to riot across the rooftops, lighting fires, vandalising structures, and throwing items at Corrections staff.

At 7pm on January 2, teams of Corrections staff entered the prison.

Fires erupted behind the barricade at the prison chapel, forcing further evacuations as fire swept through.

The riots caused “near complete destruction” of the prison.

The rioters eventually gave up on January 6.

The trial is set down for 12 weeks.