A dog walker needed stitches to his face and staples to his head after a man hit him repeatedly with a tin of pet food.
The victim was walking his dog along Station Road, Hadfield, when he was challenged by the offender who told him the animal was not under control.
After a brief verbal altercation, the offender took out a tin of dog food from a carrier bag and struck the victim repeatedly to the face and head.
The 48-year-old victim needed several stitches to a cut on his face and staples to a gash on his head.
The offender was white, about 6ft tall, of stocky build and aged between 25 and 30. He had short, blond hair and a beard at the time.
He was wearing a white shirt with blue or red pinstripes, dark jeans and dark canvas shoes with white soles.
He was also wearing a red pair of Beats by Dre headphones.
Witnesses or anyone with information about the crime – which happened at about 9pm on Thursday, July 9 – should call Derbyshire police on 101 or Crimestoppers on 0800 555 111.