A warning has been issued to cashpoint users after a card-cloning device was found attached to an ATM in Stoneycroft, Hemel Hempstead.
Herts police are investigating a suspected fraud offence after the gadget was discovered at 7.30am on Wednesday, February 27 in the Warners End precinct.
It is not known when the machine was tampered with but anyone who used the cashpoint near the time is urged to contact their bank.
A police spokesman advised: “Always look around you when using a cashpoint.
“Report to the police and the bank anyone seen acting suspiciously nearby, any signs of tampering to the cash machine or any unusual devices.
“When entering your PIN, stand close to the machine and shield the keypad, and where possible use a cash machine inside a bank or building society, as they benefit from increased security.”
Call the non-emergency number 101 quoting crime reference D1/13/1255 if you saw anything suspicious in the area, or call Crimestoppers anonymously on 0800 555 111.