A 40-year-old Chesterfield man was threatened and robbed by two men walking along a road in the town centre this week.
The man has told police officers that the men approached him on Sheffield Road, near the steps towards Flamsteed Crescent at about 4.20pm on Wednesday February 17.
A police spokesman said they threatened him and stole his wallet.
One of the men is described as in his late twenties or early thirties and about six feet tall. He was wearing a dark jacket, blue jeans and a dark baseball cap.
The other man was in his mid to late twenties, shorter than the other man and had short dark spiky hair. He wore a dark tracksuit top and jeans.
Anyone who was in the area at the time or who has any information about the offence should contact Detective Constable Julian Hall on 101, quoting crime number 7292/16, or call Crimestoppers anonymously on 0800 555 111.