One person in a serious condition was flown by helicopter to Waikato Hospital following an early morning crash near Waiouru.
Emergency services were alerted around 3.30am on Friday to the crash on State Highway 1 north of Waiouru.
A police spokeswoman said police received a report of a single-vehicle crash on SH1, between Access Road No17 and Paradise Valley Rd.
Fire and Emergency extricated one person from the vehicle.
St John sent two ambulances and one helicopter to the scene. One person was flown to Waikato Hospital with serious injuries.