Two men have attempted an armed robbery at a post office in Colsterworth, Lincolnshire.
The pair, who had been seen in a parked car outside Colsterworth Post Office, entered the store just after 10am.
One of the males threatened staff with what is believed to be a starting pistol, but both of them left empty-handed.
They were then seen to drive off towards North Witham, where they swapped vehicles.
Police have recovered the pistol, which will be subject to forensic examination, and are seeking anyone who was in the area at the time or on the roads between Colsterworth and North Witham.
Officers would also like anyone who saw anything suspicious in the days or weeks before the incident to come forward as police believe the males may have visited the area before.
Anyone with any information should contact detective inspector Mark Kirwan at Grantham CID on 101, quoting incident 121. Alternatively, contact Crimestoppers anonymously on 0800 555 111.