A woman was punched and had her purse stolen in Gold Street, Northampton, last Monday (12 September).
Shortly after midnight, the victim was standing at the junction with Bridge Street, opposite All Saints Church, when a man rode past on a bike and grabbed her purse.
The woman tried to stop him getting away, at which point the offender punched her in the arm and then rode off.
The offender is described as white, tall, with a skinny build and cuts on his face. He was wearing a grey hooded top and dark blue jeans, and was riding a large, dark-coloured bike.
Witnesses, or anyone with information, are asked to contact Northamptonshire Police on 101. Alternatively, they can call independent charity Crimestoppers on 0800 555111.