You are not permitted to download, save or email this image. Visit image gallery to purchase the image.
Senior Sergeant Roy Apperly, of the Canterbury District Command Centre, said a car and truck collided close to Whitneys Creek around 9:45am.
One person died at the scene.
Serious Crash Unit and other emergency services are in attendance.
The NZ Transport Agency advises that the highway is closed and diversions are in place.
The highway was not expected to be open until at least mid-afternoon or later, NZ Transport Agency regional performance manager Pete Connors said.
"The detour route, which is sealed and suitable for heavy vehicles, is via Old Ferry Road and Glenavy Tawai Road, just north of the Waitaki River. The detour route will not add much to the overall journey time."