A two-car crash has blocked the A11 northbound at Wymondham.
The road is blocked just after the B1135 turn-off after the incident, which happened at about 10.10pm.
Three fire crews, from Wymondham and Hethersett, responded, where they provided scene safety and helped the police and ambulance.
It is understood that a car - thought to be a red Honda Civic - crashed into the central reservation, with a 4x4 also involved, although Norfolk police could not confirm the vehicles involved.
There is debris on the road and the vehicles are yet to be recovered.
Norfolk police has tweeted advising drivers heading north to drive through Wymondham town centre.
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