Three people have been injured in a one vehicle crash on State Highway 1 near Hunterville.
Emergency services were alerted to the incident at 7.30am.
A St John spokesperson said two ambulances and a helicopter were at the scene.
One occupant is in a serious condition and has been transferred to Palmerston North Hospital via helicopter.
The two other occupants have been transported by ambulance to Palmerston North Hospital in a serious and moderate condition.