A large truck has rolled near Tokoroa blocking a lane on State Highway 1 and causing delays.
The driver has been taken to hospital.
Witness Aaron Adamson said the truck was empty and thought wind was a factor in the accident.
"He came around the corner and I believe a gust of wind pushed him off the road. It hit the bank and rolled," Adamson said.
"I believe it was the wind because I've been getting blown around in my truck today."