A card-skimming device was discovered on a cash machine in the Denny area last week.
The type found keeps hold of the customer’s card after they have entered their PIN, making them think it has been retained by the bank.
The thieves then remove the device from the ATM along with the bank card and number.
A police spokesman advised: ‘‘Everyone should be vigilant when using ATM machines. If there is anything untoward with the machine that you are not happy about please contact the us and bank immediately.
‘‘Always check the ATM machine before using it to make sure there are no loose parts to it, wires exposed, cameras pointing to the keypad, etc. Remember to always shield you PIN.’’