A man was punched and kicked by an attacker as he walked in March.
The 22-year-old man was knocked to the ground where he was attacked in Badgeney Road, near the Co-op, at 4.15pm on Saturday, September 20.
A woman driving past in a blue Vauxhall Astra sounded here horn and the attacker fled.
The victim was treated for injuries at the scene by paramedics and then taken to Peterborough City Hospital but he was not seriously hurt.
The attacker was described as white, in his late 20s, stocky, and wearing a blue hooded top and blue baseball cap.
PC Kurt Allen, who is investigating, said: “This was a nasty and apparently unprovoked attack and I am keen to speak to anyone who saw what happened. I would particularly like to make contact with the woman who helped stop the attack by beeping her horn.”
Anyone with information should contact PC Allen on 101 or Crimestoppers, anonymously, on 0800 555111.