A logging truck has rolled south of Whangarei, partly blocking State Highway 1.
Emergency services are at the scene where, according to initial reports, the driver was trapped in the cab. He has since been taken to Whangarei Hospital.
The crash occurred near the Caltex Service Station at Oakleigh.
The Ruakaka Fire Brigade has been called out due to concerns about a significant quantity of spilt diesel. At least one other vehicle is understood to have been damaged.
The accident, which occurred just after 10am, is likely to disrupt highway traffic for some time. No diversions are in place because traffic is still flowing in both directions, albeit slowly.