A man in his 30s was hit in the face while he was at work on a North Tuddenham farm.
The assault took place at 1pm on Thursday, August 16 on the Main Road.
After spotting a white panel van in the yard, the victim approached two men and asked them why they had stopped at the farm.
One of the men hit the farm worker, who did not need to go to hospital.
The two men left the scene in the van.
Anyone who has knowledge of the incident or who saw the assault should contact PC Chris Bailey-Green at Dereham police station on 101 or call Crimestoppers anonymously on 0800 555111.
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