The Southwestern Motorway in Auckland has been closed following a serious crash at about 11 50 this morning.
The crash happened in the Northbound lanes between the Puhinui and Massey Road interchanges.
Northbound traffic is being directed off the motorway at Cavendish Road to avoid the scene.
The Puhinui Road on ramp is closed. Initial reports indicate that a Northbound car struck the median barrier and rolled over.
The female driver has received serious head injuries and a passenger has less serious injuries.
They are being taken to hospital by ambulance.
The motorway is expected to be closed for several hours while the wreckage is cleared and the Police serious crash unit examine the scene for evidence.
Drivers are asked to be patient and exercise caution in the area, and if possible use an alternate route to avoid the Southwestern Motorway.