Auckland's Southern Motorway has reopened all four southbound lanes after a serious crash this afternoon, but gridlocked traffic will still take some time to clear.

A man was seriously injured after a van collided with a truck on Auckland's Southern Motorway at about 4pm today.

The accident happened between Mountain Rd and Market Rd and caused major congestion with traffic backed up through Spaghetti Junction. South-bound traffic has been reduced to one lane.

Police said that had, in turn, caused delays on the Northwestern Motorway.


The injured person was trapped in the van for some time but has now been cut free and taken to Auckland Hospital.

The NZTA's Regional Traffic Operations Manager, Kathryn Musgrave, said while the lanes had now re-opened, people should consider using alternative routes until the traffic back-log clears.

Police have also advised motorists to avoid the area or delay travel if possible until traffic can be cleared.

Were you affected by the traffic delay? Send your story, photos or video here.