The prisoner is in intensive care following the assault. Photo / NZPA
A Rimutaka prisoner is in a serious condition after being assaulted by another inmate, the prison director confirmed.
A Hutt Hospital spokesperson said the patient was in a serious condition in the intensive care unit at the hospital.
Rimutaka prison director Chris Burns said the inmate was assaulted yesterday.
He said police were advised of the incident.
Mr Burns said violence in prison wasn't tolerated and any prisoners who used violence would be held to account.
In October this year, a prisoner assaulted an officer at the Otago Corrections Facility when he was transferred from Rimutaka Prison in preparation for his parole release.
Wiremu Tamahana Allen, 33, was convicted and sentenced to three months' jail, cumulative on the term he was serving.
In June 2012, a prison officer and an inmate were in hospital in serious conditions after a brawl at Rimutaka Prison.
The Department of Corrections said a guard went to the aid of a low security prisoner who was the victim of a spontaneous assault by a group of inmates at the Upper Hutt prison.
It's understood a NZDF aircraft and multiple helicopters are involved.