Residents in Bushey have been warned about fraudsters who have been sending out legitimate-looking emails designed to trick them into installing a harmful "virus" on their computer.
OWL Watch Members have been told the emails contain information about attending a court hearing, and contain specific dates, times, locations and reference numbers.
The downloadable file actually contains a virus that allows the criminal to find out details about the victim, including stealing personal and financial information.
To report a fraud and receive a police crime reference number, call Action Fraud on 0300 123 2040 or use their online fraud reporting tool.
Local authorities send out alerts via OWL about crime and other issues happening in the area.