Auckland motorists faced lengthy delays after a crash closed northbound lanes on the Southern Motorway this afternoon.
The crash, involving a tanker truck and at least one car trapped under it, took place just after the Khyber Pass offramp.
The crash has been cleared and the lanes are now open.
One person was taken to Auckland City Hospital with moderate injuries. .
A Fire and Emergency New Zealand shift manager said they freed two people, one from each vehicle, at the scene.
A passing motorist said while one car was trapped underneath the large truck, it appeared two other cars might have been damaged by the median barrier.
"Probably trying to get out of the way," she said.
While traffic was going to be "a nightmare", it appeared those already caught in the congestion were being patient, she said.
"I think they understood it was pretty serious."
Rubberneckers were adding to the delays, she said.
The crash initially blocked three northbound lanes, causing heavy congestion.
The crash is exacerbating delays for motorists heading north due to the closure of Auckland Harbour Bridge lanes in both directions.
Traffic is now gridlocked back to Greenlane and is inching along at Ellerslie.
NZTA has advised motorists to pass the scene with care and expect delays.
Police were notified of the crash on the northbound lanes shortly after 1.30pm today.
"Motorists are advised to expect delays or use an alternative route where possible."