The A47 has been closed following a crash in west Norfolk that left a man seriously injured.
The collision happened at about 4.20pm near Little Fransham, between Dereham and Swaffham.
The road has been closed in both directions between Wendling and Necton following the incident.
In a tweet, Norfolk Police has said: "Delays are expected. Please avoid the area and find alternative routes."
Three crews from the Norfolk Fire and Rescue Service attended.
Appliances from Dereham and Watton made the scene safe and assisted ambulance crews with casualty care.
There was heavy congestion on the road following the crash.
Traffic is building up between Little Fransham and Wendling on the A47 and also on Station Road and Beeston Road.
As of 10pm on Monday (May 23) the road remained closed.
Drivers have been advised to plan alternative routes when travelling Tuesday morning (May 24).
For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
Join our Norfolk Travel Information group on Facebook for all the latest traffic news in Norfolk.
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