Lincolnshire Police were called to Queen Street in the early hours of Saturday morning (April 23) after a report of a robbery at around 12.30am.
Firearms were deployed to the scene as a precaution, and the street was cordoned off by officers while the incident was ongoing.
Queen Street has since been reopened and two men have been arrested in connection with the incident.
Lincolnshire Police personnel will remain on the scene as police carry out further investigations, but officers have confirmed there is no threat to the public.
A spokesman said: “If you think you have information that can help us, you can get in contact with us in one of the following ways – call 101, quoting incident number 10 of 23 April, email [email protected] or call Crimestoppers, anonymously, on 0800 555 111 or report online at https://www.lincs.police.uk/.”