A man's neck was sliced with a scalpel-like blade as he was stood near the Racecourse in Northampton.
The 20-year-old victim was attacked at about 3.15pm yesterday (Monday, March 27) outside the Jade Restaurant.
He suffered a cut to the neck as well as being punched in the face.
The attacker was described as white, aged about 26 years old and was seen to be wearing a yellow jacket.
He was also described as 5ft 8in with short, black hair.
Anyone with information should call Northamptonshire Police on 101 or Crimestoppers, in confidence, on 0800 555111