An early morning crash which killed two people and left two others in a critical condition was caused by a vehicle travelling 10km in the wrong direction.
CCTV footage has confirmed the offending vehicle had entered the Wellington Urban motorway northbound lanes at Petone.
Two vehicles collided in the northbound on the fly-over between Molesworth St and the Aotea on-ramp, at about 4.20am.
Two people died at the scene and the two in the second vehicle were taken to Wellington Hospital. One is in a serious condition in ICU, and the other is undergoing treatment, said a spokesperson.
After reviewing CCTV police have confirmed the vehicle in which two people died had entered the motorway by turning right into a northbound lane from Cornish St in Petone.