A section of the southbound lane on State Highway 20 near Māngere East in Auckland has reopened after a crash.
NZTA said the crash, which happened about 6.30pm and involved a motorcyclist and a car, was causing delays near the Portage Rd overbridge.
While the motorway has reopened, motorists are being asked to avoid the area or consider travelling via SH1 to go south.
Police asked motorists to remain patient while the backlog of traffic cleared.
The motorcyslist sustained serious injuries and has been transported to hospital.