Three men have been arrested following an attempted robbery at a newsagents on Newark Road.
The incident happened at Londis at around 10.44pm on September 3.
Offenders entered the shop and threatened a staff member before demanding cash.
The male shopkeeper was then given a blow to the head, but was later treated for a minor injury. No cash was taken during the incident.
Officers arrested two 22-year-old local men at the scene, and one 23-year-old local man a short time later, all in connection with the incident.
They have been released on police bail pending further enquiries until December 5.
Anyone who saw any activity in the area should call DI Nikki Mayo, quoting incident number 458 of September 3 via 101 or Crimestoppers anonymously on 0800 555 111.