A girl was walking along Kempston Road at around 5.15pm when a group of four men approached her. They assaulted her, punching and kicking her to the floor before stealing her rings.
Two of the offenders are described as white, and the other two men were described as mixed race. All were wearing dark clothing.
PC Emma Cook, investigating, said: “This unprovoked incident has understandably left the victim shaken and it is not acceptable. We are committed to tackling this nasty crime and we urge anyone with information that could assist our investigation to come forward.”
Anyone with any information should call PC Cook on 101 or Crimestoppers, anonymously, on 0800 555111.