Three people have died and another is in a critical condition after a crash at the Kopu Bridge, near Thames
Emergency services were called to the south side of the bridge near State Highway 25 about 8.30pm.
Police said two cars were involved with two people in each.
Diversions are in place at the Kopu roundabout and at the intersection of State Highway 25 and Hauraki Road.
The road is expected to remain closed until at least midnight.