The incident happened at around 10am, and police closed the road between the A186 Holystone and A1058 Silverlink junctions.
Police and the fire service were called to the scene, and the Great North Air Ambulance was also in attendance.
Diversions were been put in place, with northbound traffic advised to follow signs with a solid triangle, and southbound the hollow diamond ones.
The northbound lanes were reopened by 11am, but southbound remained closed while police accident investigators examined the scene.
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