More details have emerged about an attack against two prison officers at Waikeria Prison over the weekend.
Both guards were hospitalised with head injuries, inflicted in a surprise attack by two inmates trying to escape.
Police have yet to lay charges in relation to the attacks.
Department of Corrections chief executive Ray Smith says the prisoners were armed with metal bars probably fashioned out of furniture, and the attacks came without warning.
Mr Smith says one officer took a terrible beating over the head, but fortunately both are recovering well.