The head of Corrections says guards at Mt Eden Prison have told him the biggest problem at the prison is understaffing.
Corrections has formally taken over the management of the prison from private operator Serco while a string of allegations - including a fight club, contraband, prisoner injuries and the death of an inmate - are investigated.
The department has also fined Serco $500,000 for not meeting performance targets.
Over the weekend, it emerged that further questions were being asked about the circumstances of a second inmate's death.
Corrections chief executive Ray Smith said he met with staff and prisoners today.
He said the biggest complaint was about staff rosters not being properly filled, which meant there was less ability to deal with any problems.
"The main issues is about getting staffing and the management of staffing correct. So making sure that when rosters are posted, they actually get filled, so if people are away sick then they need to be replaced," he said.
"Those are the types of things people have raised with me. I mean, I was only there for a short while; I'm sure they're not going to raise everything with me but they can with the Chief Inspector [of Prisons]."
He said the department was trying to understand whether the violence at Mt Eden Prison was an unusual spike in violent behaviour.
"In all prisons, there are violent incidents, and sometimes you get spikes. I think what we want to get underneath is whether we're seeing something particularly unusual here.
"Remember, we saw those fight club videos. I think we all felt concerned when we saw those. When I saw those, they made a lot of sense to me [in terms] of things that people have often worried about."
Serco faces $500k in penalties
Mr Smith said this morning that Serco would face financial penalties of $500,000 for not meeting performance targets.
"I'm likely to sign off half a million dollars of penalties this morning, so I'm going to head in and do that before I head off to Auckland today.
"We haven't worked our way through all of that yet, we need to review all of the footage and get better understanding of some of the incidents, but I expect more penalties to follow."
Mr Smith said that penalty only related to the last financial year and further fines were likely after the recent allegations had been investigated.
He said 20 experienced Corrections managers would be at the prison for at least the next week to support the current staff and Serco would bear the costs of bringing them in.
"They're keen to be here and get in and give a hand. But let's understand what the Serco staff need.
"That's what my team will be doing - understanding what they need and and working out how we can support them to do their jobs well."
He also said a normal routine would be restored at Mt Eden Prison this week.
Mr Smith told Morning Report a full lockdown search on Friday yielded a few cellphones and improvised weapons.
"I think they got four or five cellphones and they picked up a few sort of 'shanks', where people had fashioned weapons out of items... I'm not aware that any drugs were found.
"But I'm going to be there today so it'll give me a chance to see exactly what they've found."
Mr Smith said a final warning needed to be given before Serco's contract was terminated.
Corrections Minister Sam Lotu-Iiga said he was unhappy with the flow of information from Serco and Corrections to his office, and would be speaking with Mr Smith today.
After a brief crisis management visit to New Zealand last week, Serco managing director Paul Mahoney has returned to Australia.
Corrections just saving face - union
While Corrections takes over the running of the prison today, the union representing prison officers said the move was more about saving face than stepping in.
Corrections Association industrial officer Beven Hanlon described Serco being put on notice as "heartwarming''.
But he said steps required to remove Serco had not even begun yet - the first would be a written warning.
"Looking at the contract that Serco have with the Government, this is really just a whole lot of rhetoric.
"So when somebody says you're on notice, I would expect that they've been warned in some way.
"So unless they've got it in writing, nothings happened," he said.
The Labour Party's Corrections spokesperson, Kelvin Davis, agreed.
"The Government's just using weasel words to down play the situation to try and divert the country's attention.
"So if anything comes up in the meantime, they'll say look we're just having a review into the whole situation.
"Like I say, people's attention spans will wane and something else will pop up, you know the Rugby World Cup is a couple of months away," he said.
In a statement at the weekend, Mr Mahoney said he understood all allegations and issues in respect of Mount Eden Correction Facility would be reviewed by the Chief Inspector of Prisons and overseen by the Ombudsman.
But Mr Hanlon said the inspectorate was too close to the chief executive of Corrections to run an effective investigation.
"The prison inspector is anything but independent. We understand he is on the same floor as the chief executive who is his boss, so they can knock on each others door to see how things are going, it's not an independent review."
Deaths at Mt Eden
The prison inspectorate is already looking into Nick Evans' death at the prison - one of three cases which have brought Serco under intense scrutiny.
Mr Davis has also questioned the handling of another case at the prison in which a man died after being violently bullied.
Mr Smith said Corrections was hoping the Chief Inspector of Prisons' report into Mt Eden Prison would be completed by the end of August.