Lincolnshire Police are looking for witnesses after an armed robbery at a city newsagents in south Lincoln on Tuesday morning.
The incident happened at around 4.40am on May 7 at McColls Newsagent at the Lowfields Centre, off Brant Road.
A 30-year-old man taking the daily newspapers inside was approached by the offender and threatened. He was forced into the shop and threatened with a firearm. The offender then stole several thousand pounds.
The staff member is shaken but was not hurt in the incident.
The offender is described as white, around 6ft tall and of stocky build. He spoke with an Eastern European accent, and was wearing blue overalls and a balaclava.
Police are appealing for anyone who recognises the description of the man or saw any suspicious activity in the area around the time to get in touch.
Anyone with information should call DS Jen Lovett at Lincoln CID via the 101 police number, quoting incident number 50 of May 7, or call Crmestoppers anonymously on 0800 555 111.