Waikato police are seeking the driver of a ute, who drove off after the vehicle collided with an ambulance.
The incident happened on Hinuera Road, just south of Matamata, just after 5pm on Tuesday.
The ambulance, which was travelling below the speed limit with its lights flashing, was taking a patient with head injuries to hospital.
The police say it appears the ute's driver lost control on a bend and crossed the centre line.
There was no further injury to the patient.
The vehicle is described as a dark grey or blue Toyota Hilux type, and is likely to have some frontal and side damage.
