The Corrections Department says prisoners stuck on a broken-down bus on the Desert Road in the central North Island smashed windows and damaged its interior after becoming restless.
The bus was carrying 20 prisoners, including two with a maximum-security classification, on Wednesday night.
Corrections says the breakdown was due to a hydraulic fault and took two hours to fix.
Acting National Commissioner Jeanette Burns says the bus was travelling from Tongariro-Rangipo Prison to Rimutaka Prison near Wellington when it broke down on the side of the Desert Road 40 minutes into the trip.
Ms Burns says extra staff from the Tongariro jail were sent and police, including a dog handler, provided back-up support.
Action is being taken against the prisoners who damaged the bus and a police investigation is underway, she says.
