A man swung a metal bollard in the direction of two other men during a public disorder incident in Grantham.
The incident happened at the Isaac Newton Shopping Centre in Grantham at 11.30am on February 5, but fortunately nobody was injured.
Lincolnshire Police released an image on March 8 of a man who officers believe may be able to assist with their investigation.
The force want to identify him as part of their inquiries, but did not specify whether or not he is considered as a suspect or a witness.
Anyone with information, or who recognises the man in the image, should contact police on 101 or via email at [email protected] quoting reference 123 of February 5.
Alternatively, it can be reported through the independent charity Crimestoppers anonymously on 0800 555 111 or online here.