A Hato Hone St John spokesman said they sent an ambulance, rapid response unit and an operations manager to Auckland Prison just after 9.46am.
The prison’s general manager Stephen Parr told the Herald three prisoners have been secured and would be put on directed segregation.
Staff immediately secured the alleged offenders and gave the victim first aid, Parr said.
He said Corrections would carry out a review into the incident and all evidence would be handed over to police.
Parr said he did not tolerate prison violence.
“Anyone who resorts to this behaviour will be held to account,” he said.
“We are constantly working to ensure our prisons provide the safest environment possible for staff and prisoners. Auckland Prison is New Zealand’s only specialist maximum-security facility, and accommodates the country’s most dangerous and volatile prisoners.
“Our staff manage some of New Zealand’s most dangerous people in a complex and challenging environment.
“Over 80% of the prison population have convictions for violence in their offending histories, and more than 90% have had a lifetime diagnosis of a mental health or substance abuse disorder.”
Raphael Franks is an Auckland-based reporter who covers business, breaking news and local stories from Tāmaki Makaurau. He joined the Herald as a Te Rito cadet in 2022.
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