Drivers have been urged to avoid the A140 following a crash in Stratton Strawless near Hevingham.
The road is currently blocked and police and ambulance crews are on the scene.
It is believed three vehicles are involved.
Diversions are in place on the Aylsham side and work is underway to divert traffic on the Norwich side.
Norfolk Police tweeted at 2.12pm, asking people to "please avoid the area".
The road is currently blocked and traffic is building along the road.
For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
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