PC Jamieson, based at Helensburgh Police Office, is investigating the incident, which occurred between 2pm and 4.30pm on April 2.

A spokesman for Police Scotland said ‘communal mailboxes’ within a close at an address at 70 West Clyde Street, Helensburgh, were forced.

He added: “If you think you can assist with this enquiry please contact the police on 101 or call Crimestoppers on 0800 555 111.”