The road was closed between the A186 Holystone and A1058 Silverlink following what police described as a 'serious road traffic collision'.
Northumbria Police, North East Ambulance Service, Tyne and Wear Fire and Rescue Service and the Great North Air Ambulance were at the scene.
Both north and southbound were closed but, after the Air Ambulance left the scene, northbound was reopened.
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Highways England said diversions were in place.