An overturned lorry was causing slow traffic on the eastbound carriageway of the A47 at the Easton roundabout.
Part of the A47 has now been closed for recovery work.
Police attended the scene of an overturned lorry, which is blocking the eastbound carriageway. The incident is believed to have taken place just after 3.30pm.
They are urging drivers to avoid the area if possible.
Congestion was tailing back to Honingham as traffic is taking turns to pass the scene.
Fire crews from Sprowston, Earlham, Carrow and Hethersett attended the scene to release one casualty from the lorry.
Injuries are unknown at this point.
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