Site emergency response teams (Sert) will respond to threats and incidents at prisons throughout New Zealand, following a successful trial at Spring Hill Corrections Facility, in Waikato, last year.
The teams have powers to self-approve the use of pepper spray and carry out raids for weapons, drugs and other contraband.
Corrections confirmed a Sert would be operational at the Milburn prison in three months.
Statistics released under the Official Information Act revealed 273 assaults occurred in the facility (OCF) from July 2010 to June 2015. A further 21 assaults had taken place in the first four months of the 2015-16 financial year.
Of the incidents, 204 were prisoners assaulting other prisoners, 83 were prisoners assaulting Corrections staff and seven were prisoners assaulting people other than staff or other prisoners.
Prison reform campaigner Roger Brooking said the numbers were concerning and demonstrated the prison's ‘‘appalling track record'' of prisoner care.
‘‘They are concerned far more about how safe staff are, and they should be safe, but I think there is far less concern for the safety of prisoners,'' Mr Brooking said.
‘‘Staff are treated as human beings, while prisoners are treated basically as animals and I don't think Corrections cares, unless it gets in the media.
‘‘There's a lot going on around the country, including [at] OCF, that we never hear about.''
Corrections Association of New Zealand president Alan Whitley said assaults were rising at prisons throughout New Zealand.
‘‘Forty percent of prisoners in prison now are in there for violent crime,'' he said.
‘‘They don't all of a sudden become well-behaved prisoners when they get locked up in there.''
The prison population was also growing, which put more stress on the system.
As a result of the issues, all association members were now issued with stab-proof vests.
He also backed the formation of the Sert at the prison.
‘‘They will be in the process of doing selection for it very soon,'' he said.
‘‘That's something we have supported for a long time.''
Otago Corrections Facility prison director Jack Harrison said in addition to establishing the Sert, all custodial staff received specialist training in tactical communications, de-escalation and negotiation and had access to protective equipment.
Corrections said the prison population rose to 9000 for the first time in August last year.
It reached more than 9360 in February 2016 - a record high - and at February 22 the prison muster was 9279.
The statistics released by Corrections also revealed 314 prisoners had been taken to hospital during the period from July 2010 and there had been 133 discoveries of weapons.
The use of mechanical restraints and force were also on the rise with 41 instances of force being used in 2014-15 - more than five times any other year in the released statistics - and 72 instances of the use of mechanical restraints - well above the previous highest total of 58 in 2011-12.
Mr Brooking said it pointed to a concerning culture at the prison.
‘‘Historically, I think they have had an appalling track record in terms of not only managing violence among the prisoners, but also their healthcare,'' he said.
‘‘The coroner has made recommendations to fix things and nothing has changed. It's all just talk.''
The coroner was investigating two deaths at OCF in recent months, both understood to be suicides.
