Truckies are being advised to take a break after a trailer overturned on a diversion route set up following a fatal crash on SH1 in Putaruru last night.
Diversions were in place on Main St, Princess St and Lichfield Rd after one person died following a collision involving two cars at about 6pm.
After 9pm, police were advised that a trailer had overturned on Lichfield Rd - part of the diversion route.
That route is now down to one lane, and only passable by cars. It will take some time for the scene to be cleared, police said.
Truckies are advised to sit it out until the first crash scene is cleared and State Highway 1 reopens - expected to be by 11pm.
The police are investigating the earlier crash.