A man was taken to hospital with facial injuries after being assault in Bletchley Town Centre on Saturday afternoon.
Thames Valley Police are now appealing for witnesses to the incident which happened outside the Wilkinsons shop at about 4pm.
The victim, a 43-year-old man, sustained a large cut to his forehead and was bleeding heavily from his nose and head.
He was taken to Milton Keynes Hospital and was later released.
The offender is described as a white man, aged in his 40s, who was balding.
Contact PC Jim Bishop from Milton Keynes police station on 101 if you have any information.