A Serco staff member working at Auckland's Mt Eden prison has been suspended after a security camera recorded him fighting with a prisoner.
The private prison operator has confirmed the officer has been relieved of duties and is going through a disciplinary process .
In a brief statement confirming the incident, Serco said: "The Chief Inspector, with the independent oversight of the Ombudsman, is carrying out an investigation into issues and allegations at MECF (Mt Eden Corrections Facility). This includes allegations of organised fights.
"The safety and security of staff, prisoners and visitors in MECF is paramount and we have zero tolerance for violence. An officer has been suspended, pending a disciplinary hearing."
The Corrections Department, which is now overseeing the remand prison, is refusing comment other than to say inmates and staff were being interviewed and CCTV footage reviewed as part of the investigation into events at the prison by the Chief Inspectorate.
Last month, Corrections announced it was appointing a director to manage the day-to-day running of the remand jail as several allegations were investigated.
These included prisoners participating in organised fights - known as fight clubs - which were filmed on smuggled smartphones.
'A wake up call'
The Labour Party's Corrections spokesperson said he was not surprised by the latest revelations to come out of Auckland's Mount Eden Prison.
Labour Corrections spokesperson Kelvin Davis said the allegations proved to be true, it should be a wake up call for Government.
"I just hope that the review isn't a review on how to tidy up Mt Eden so that Serco can take it back over.
"I hope it's a review that proves that the Serco experiment has failed, their contract needs to be torn up, and they need to be kicked into touch."
Corrections Minister Sam Lotu-Iiga said he was aware of a number of allegations involving the privately run Mount Eden Prison in Auckland and had previously expressed concern about them.
He would not comment further on the latest allegations.