Three people have been injured, two critically, after a car swerved across a busy highway and ploughed off the road.
A police spokeswoman said the crash happened on State Highway 1 near Pokeno about 6.40am.
"The car swerved across the lanes and into the side of the road," she said.
The Waikato Expressway has been closed in both directions at Pokeno after the crash.
Three people were inside the wrecked car, which had been heading south.
Two were critically injured and one was seriously injured.
The spokeswoman said only one was car involved and many motorists on the highway witnessed the crash.
Ambulance and fire were at the scene.
The Serious Crash Unit was investigating and the road will be closed until at least midday.
Diversions are in place through Pokeno, police said.