Emergency services are attending a serious crash at Warkworth.
Police were called to State Highway One at Windy Ridge south of Warkworth shortly after 1.30pm. Officers arrived to find one person in a serious condition.
The road is closed to enable emergency services to remove the person from the vehicle.
Ambulance have sent a helicopter to assist and serious crash investigators are making their way to the scene. Northbound motorists are advised that if they want to avoid the road closure they should take the alternative north route onto SH16 from Silverdale.
Traffic travelling south should divert from Warkworth end onto Woodcocks Road via SH16.
Inspector Kerry Watson said congestion is very heavy north and south of this scene and will be for some time.
Police said SH1 at Windy Ridge reopened about 3.30pm.
There was still considerable congestion in the area which was expected to take some time to clear.