The A11 was closed following a three-vehicle crash about a quarter mile from the Thickthorn roundabout on the Norwich bound carriageway.
Police were called to the scene at approximately 2:15pm.
Eyewitnesses reported a vehicle overturned on the carriageway.
Four fire engines from Sprowston, Carrow, Attleborough and Hethersett were called to the scene and arrived at 2:31 pm. Casualties were taken into the care of the ambulance service and minor injuries have been reported.
Police advised people to avoid the A11 and the road was closed northbound. The road reopened at 4:17pm and traffic is reportedly flowing well again.
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