A man had part of his finger bitten off during an assault in Rothwell in the early hours of Sunday, November 30.
The incident happened near the Red Lion Hotel, just off the Market Square, at about 1am.
The 46-year-old victim was attacked by four men who punched and kicked him – with one of them then biting part of his finger off.
The victim was taken to Kettering General Hospital for treatment.
Police have described the main attacker as white with red hair. He was wearing a white shirt.
The assault was broken up by passers-by and the suspects ran off in the direction of Bell Hill, to the east of the Market Square.
Police believe the incident is related to an altercation inside the Red Lion. Anybody who witnessed this, or the assault outside, is asked to contact police.
Witnesses, or anyone with information, can call Northamptonshire Police on 101 or Crimestoppers anonymously on 0800 555111.