A truck has flipped near Atiamuri and blocked State Highway 1.
Emergency services are at the scene. The driver reportedly walked away with only minor injuries.
A police communications spokeswoman said the crash happened on State Highway 1, just south of the intersection of State Highway 30, about 12.30pm.
Rotorua Daily Post staff are at the scene of the crash.
Traffic is backed up on State Highway 1 and police are turning motorists around.
Trucks are having to reverse several hundred metres because they can't turn around on the narrow stretch of road.
Police said managed road diversions were in place. There are seperate diversions for north and south-bound traffic due to the secondary nature of the diversion roads.
South-bound traffic is being diverted down SH30 onto Ohakuri Road while north-bound traffic is being diverted onto Ongoroto Road.
Motorists are advised to avoid non-esstential travel in the region of the crash.