Prime Minster John Key says he's troubled by videos which have emerged of prisoners apparently engaged in 'fight clubs', as well as being involved in taking drugs and alcohol.
Mr Key, who has returned to New Zealand from holiday while Parliament has been in recess, says the Government has a duty to keep prisoners safe.
Two reviews – a Serco and a Government-led inquiry- into cellphone videos uploaded to the internet showing prisoners fighting, drinking and taking drugs while in prison cells are currently underway.
A senior boss from Serco, the privately-owned company that manages Mt Eden Prison where the footage is believed to have been shot, has flown in from Australia to take charge of the troubled facility.
Mr Key says while he wouldn't comment on the case until the two-stage Government review is underway, what he's seen is concerning.
"In the end we have a duty of care, I would have thought as a government, to make sure people are safe in prisons as best we possibly can.
"I don't know the circumstances behind or how widespread it is or where it's actually happening, but we want to get to the bottom of it," he said at his post-Cabinet press conference yesterday.
Mr Key had been told by Corrections Minister Peseta Sam Lotu-Iiga's office there may have been an earlier report into the fight club on Sunday night.
"I don't know how far up the food chain it went. I think there are being questions asked about how high it went and ultimately whether actions were taken to bring it to senior management if it wasn’t, but in the end we'll need to get some answers to that. I don't have those today."
If the issue was as "black and white" as someone not doing their job and passing the report up the chain, Mr Key said it would be "a pretty serious issue".
The first part of other Government review is expected on August 28, while the second is due on September 30.