At around 9pm on Monday, September 11, graffiti was sprayed was sprayed on to the shutters of Highbury Post Office in Highbury Road.
A spokesperson for Hertfordshire Constabulary said: “We have released the image of a man we would like to identify following criminal damage in Hitchin.
“The man in the image was thought to be in the area around the time of the incident and could be able to assist with the investigation.
“Anyone who recognises the man is asked to email PC Hugh Roper via firstname.lastname@example.org.”
Information can be reported to police online at www.herts.police.uk/ro/report or by calling the police’s non-emergency number 101, quoting crime reference 41/73100/23.
Hertfordshire police’s web chat function can be used by visiting herts.police.uk/contact.
Anonymous information can be given by contacting Crimestoppers on 0800 555 111 or via crimestoppers-uk.org.