Drivers are being asked to avoid the A11 at Roudham, near Thetford, because of a vehicle fire which is causing huge tailbacks.
Two fire engines, one from Thetford and the other from Attleborough, were called at 11.27am and are currently on scene.
Northbound traffic is being affected and eye witness reports say there is heavy traffic.
Norfolk Police have tweeted to ask drivers to avoid the area if possible.
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