Police have arrested a man suspected of punching and kicking another man in a violent robbery.
An eyewitness saw the emergency services attend a block of flats on Portland Street just before 5pm on July 3.
The victim was taken to hospital for treatment, but his injuries are not thought to be life-threatening.
Lincolnshire Police arrested a man on suspicion of robbery in connection with the incident on July 4.
Anyone who has information about the police incident is being urged to call 101, quoting incident 358.