Drivers were urged to avoid a part of the city after a pedestrian was hit by a car.
Police and ambulance crews dealt with the incident which happened near Constitution Hill in Norwich just after 3.30pm on Thursday afternoon.
The pedestrian was taken to the Norfolk and Norwich University Hospital with a serious leg injury.
In a tweet, police advised that road closures in the area could be in place for some time.
The road reopened at 5.17pm.
For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
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