Auckland drivers are advised to use the Southwestern Motorway to get to the city due to a crash near Greenlane which has caused major issues for northbound traffic.
The traffic jam on the Southern Motorway stretched as far back as Highbrook after the crash, which happened just before 3.30pm and brought the motorway to a standstill.
The crash was cleared from the motorway around 4.45pm but police have warned motorists to avoid the area and use State Highway 20 if possible.
One motorist told the Herald a small silver car appeared to have sideswiped the central median barrier and had a smashed front windscreen.
As she approached the crash, a police officer stepped out from the left-hand side of the motorway and signalled for the cars to stop.
He and another man - possibly a member of the public - then "half-carried, half-dragged a woman kicking and screaming across the road to the police car", she said.
Traffic on the motorway was almost at a standstill before the crash site, she said.
Police confirmed they were attending an incident near the Greenlane overbridge.
"The right-hand lane is currently blocked causing significant delays and we advise motorists to avoid the area if possible," a spokesperson said.
"Further information will be available as it comes to hand."
A second accident on the Southern Motorway near the Karangahape Rd overbridge has also slowed traffic heading south.