Corrections bosses are defending the security of safe areas within prisons following a riot which saw prisoners set cleaning products and blankets alight.
Several investigations were under way into how a fight between two prisoners escalated into a full-blown riot involving 27 people earlier this month at Spring Hill in the Waikato.
Corrections Minister Anne Tolley this morning told Parliament's law and order select committee she was confident of the way the situation was managed.
She also applauded the bravery and heroism shown by staff who risked their own lives to rescue prisoners, some of whom continued to fight their rescuers.
"Our prison officers risked their lives to go in when the Fire Service said it was dangerous and they needed to to get out from locked cells prisoners . . . and remove the rioters as well."
But questions have been raised about how the prisoners were able to break into a secure staff hub and access sports equipment and cleaning products.
The 27 rioting prisoners were among 44 let out of their cells on the Saturday morning to clean them and had access to mops and brooms which they turned into weapons.
They also got hold of volleyball posts and cleaning products which they used to set blankets on fire.
A further 44 prisoners remained locked in their cells during the riot. It took 10 hours to get the situation under control with the response teams being forced to enter earlier than they otherwise would have because of the fire.
Regional Commissioner Jeanette Burns said corrections officers initially tried to calm the rioters, but when they couldn't get them under control they retreated to the staff base.
The prisoners then began attacking the base, the officers escaped to safety before the prisoners breached the base by smashing windows.
Burns said the staff did exactly what they should have done and the base was only intended to protect them for as long as possible before they could retreat further.
"The fire is what caused most of the damage to the staff base," she said.
"Some windows were broken with the volleyball posts, but in fact most of the damage was done by fire.
"This was a top-of-the-line facility, it's one of the newest facilities and again if the inquiry shows that that's not quite enough that we need in that area, then we will have to look at that."
Four trained teams wearing body armour and helmets, and armed with shields and batons, were eventually sent in and all prisoners were evacuated.
By that stage the building was full of smoke and the ceiling was falling down in places.
Corrections chief executive Ray Smith said there was always a risk of incidents in prisons but they had received no intelligence about the riot beforehand.
While some gang members were involved it was too early to say whether gang rivalry sparked the event.
And Smith said it was too early to speculate what may have caused the riot, although it was often small things that set prisoners off.
Smith also refused to comment on suggestions the sprinkler system had not worked as well as it should have.
The sprinklers had gone off and their effectiveness would form part of the investigations, he said.
His focus was on learning from what had happened.
"The people who started the incident were essentially going to burn to death in it," he said. But there was never a risk to public safety.
Taking away all activities and equipment would create a more hostile environment and a balance had to be struck between rehabilitation and security, he said.
The 117 prisoners normally housed in the damaged wing had been moved to other North Island prisons.
The damage was expected to take six months to repair and to cost millions of dollars, meaning a delay in plans to refurbish units of other prisons around the country.
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