Prisoner critically injured in altercation

Upper Hutt CIB is investigating an altercation between two Rimutaka Prison inmates which has left one of them critically ill with head injuries in Wellington Hospital's intensive care unit.

Detective Sergeant Tony Heathcote, Upper Hutt CIB, said the assault is potentially life threatening and happened on Sunday following a dispute between prisoners playing pool.

"The circumstances of what happened and who is responsible for the injuries are being investigated by police and the Department of Corrections," he said. "We have completed a scene examination at the prison and will be speaking with inmates of the prison unit where the serious assault happened."

Detective Sergeant Heathcote said the investigation will take some time.

No charges have been laid at this stage.