Police are appealing for witnesses after a man was assaulted in Francis Jetty, off Bridge Street, during a night out in the town.
Between 2am and 3am on Saturday, October 22, the victim and another man were in the alleyway when someone shouted racist abuse at them.
As the victim turned around, he found he was surrounded by "about seven people," a police spokeswoman said.
One of them punched him in his face, resulting in the loss of three teeth.
One of the men in the group is described as white, about 6ft tall, with a medium build and short, fair hair that was swept over. He was wearing jeans and a white T-shirt with a unicorn logo on the left chest area. He had a damaged right ear.
Francis Jetty is an alleyway that runs from Kingswell Street to Bridge Street and is frequently used by people walking to and from St Peter's Way car park into town. It runs down the side of Revolutions Bar on Bridge Street.
Officers are appealing for witnesses and are asking anyone who was in the area in the early hours of October 22 and may have witnessed the incident to contact them.
Anyone with information is asked to contact Northamptonshire Police on 101. Alternatively, they can call the independent charity Crimestoppers anonymously on 0800 555 111.