A member of staff at a Wellingborough shop was threatened with a knife.
Police have released a CCTV image of a man they want to speak to after the incident at Super Shop newsagents in Park Crescent.
The incident took place between 12.20pm and 12.30pm on Thursday, April 11, with police releasing the image today (May 15).
A man entered a store in the area and threatened a staff member with a knife. A member of the public then walked into the store and the man ran off.
The man in the image or anyone who recognises him should call Northamptonshire Police on 101.
Information can also be shared anonymously via Crimestoppers on 0800 555111.