Drivers have been hit by heavy delays on part of the A47 after "human waste" was spilled on to the road.
Police has closed part of the A47 in Hockering towards Dereham after the incident which happened at about 8.50am on Tuesday (October 18).
The road has been closed from the Honingham roundabout.
A lorry, which is thought to have been involved in the incident, has come to a standstill in the middle of the carriageway.
A police spokeswoman said: "Environmental Agency will be informed as it is believed it could be human sewage.
"It remains unclear at the moment exactly how this has happened."
Officers remain at the scene as of 1pm.
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