A Corrections officer has described how a high security prison unit slowly became engulfed in flames, as prisoners laughed and “yahooed” among each other.

The staff member, who has name suppression, says at one point she saw a prisoner sitting on another inmate’s shoulders, using an item to smash their way through the ceiling and onto the roof of the exercise yard they had been in.

Eleven men are on trial in the High Court at Hamilton facing a variety of charges, including rioting, arson, assault with a weapon, and aggravated burglary from a riot between December 29, 2020, and January 3, 2021.

Peter Te Hau, Te Reneti Tarau, Taimana Soames, Hone Ronaki, Beau-James Paul, Christopher Ranapia, Siaumau Lote Telea, Ian Larkins, Leon Huritu, Bronson Keil, and another with name suppression, deny the charges.

Keil, Telea, Soames, and the man with name suppression face additional charges of riotous damage and arson after allegedly damaging property and lighting fires in exercise yard 116.

Ronaki also faces a charge of threatening to kill a prisoner who left the alleged rioting group on the morning of December 30.

Six others have previously pleaded guilty and are awaiting sentencing.

The staff member was working in the East South wing on the morning of December 29, 2020.

About 21 prisoners were moved out onto exercise yard 116, and patted down or checked for contraband.

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The staffer described how an officer spotted a razor blade in the shower area, and mentioned it over the radio.

Razors were issued on set days of the week or given to prisoners if they were due to see a visitor.

She went down to what is dubbed “the grille”, or the entrance to the yard, with another senior officer.

“I just asked them what’s going on, where’s the razor, give me the razor.”

Nothing was handed over, so she asked again, “don’t be silly, just give me the razor”, she said.

A prisoner replied that he didn’t have one, she then threatened to “run the yard in” or return all 21 of them to their cells.

More prisoners surrounded the grille, who were talking over each other, saying it was unfair to run the yard in for just one or two prisoners.

“I said ‘that’s how it is, you know that’. I said ‘give me the razor and we will go on our way.”

She recalled Bronson Keil say that “it wasn’t fair, we haven’t got the razor, we shouldn’t be run in”, while the man with name suppression was just swearing at her.

They still refused so she left, and gave them 5 to 10 minutes to mull it over. When she returned a prisoner handed it over and said he’d flushed a second down the toilet.

All was well until she heard a Code Blue announced over the radio in yard 116 due to a fire.

Corrections staff were already at the gate and she heard “a lot of noise, a lot of ruckus” and could also smell smoke.

Asked what sort of noise she could hear, the staffer said, “laughter, just a lot of laughter, a lot of shouting at each other”.

“Just general noise when they’re excited or doing some together.”

By that stage, the prisoners had their faces covered with bits of clothing and she saw a small fire up in the ceiling of the yard, by the security cameras.

“They were just walking around laughing at each other, with each other.

“We were trying to engage with them to find out what was going on. They wouldn’t talk to us.”

Staff tried to get just one prisoner to talk with them, but they were told to “f*** off”.

Other Corrections staff had grabbed a nearby hose and were using it to help put out the fire out.

By that stage, she asked the prisoners to, “put the fire out, don’t be stupid, cut it out … we were trying to give the opportunity to stop”.

A Code Red was then announced which involved the evacuation of the prison as the smoke grew.

“The initial fire was getting bigger. The boys … were using rubber mats, from in the shower area, they were against the grille to block our view, I suppose.”

The prisoners were also using planks of wood against the grille but the more they tried to put the fire out, the more fires were being lit.

Asked what sort of noise she could hear, the staffer said, “screaming, yahooing, laughing”.

The sounds of property breaking were also intensifying, which included pieces of wood along with plastic from the roof.

“Little things” including an unknown liquid and bits of stone and wood, began then being thrown at the grille.

She moved up to the bridge and saw a prisoner sitting on another’s shoulders, using an item to smash their way through the roof.

 “Officers were yelling at them to get down, get off there, but they just carried on.”

The prisoners eventually broke their way onto the roof of the century bridge, and the guard room which was adjacent to the yard.

“Eventually someone broke through and the staff that was on the bridge at the time, exited … because they could see a person had broken through the fence.”

The guard room was also evacuated and she could then hear the toilet being smashed and “just yahooing” from those involved.

The prisoners then moved onto the roof above the cells on the top floor of the East North wing.

The staff member’s evidence continues.