Drivers have been warned they could face disruption due to an overturned tractor.
The Norwich-bound A146 near the A47 Trowse junction is down to one lane due to the crash, which happened at just before midday on Wednesday (March 17).
South Norfolk police said that two lanes of the city-bound road had been closed for safety reasons and so the damaged tractor could be recovered.
Police urged drivers to approach the scene slowly and pass with care.
Norfolk police said an ambulance had been called as a precaution, but the driver did not appear to be injured.
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