A prison officer and an inmate are in hospital in serious conditions after being set upon during a brawl at Rimutaka Prison this morning.
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.
The prisoner and guard were taken to hospital with serious injuries.
Other staff members who intervened were treated by prison health services.
Corrections was now investigating to determine the cause of the assault, Department of Corrections chief executive Ray Smith said.
