The device was recovered from a TSB cash machine on Lancaster Road on Sunday 5 February, say police.
According to Action Fraud, a skimmer is a small device that fits over the card slot and is made to look like a normal part of the cash machine.
Skimmers copy information held in the magnetic strip of a card when it is inserted into a machine.
Action Fraud offers the following advice when using a cash machine: "Check a cash machine every time you use one. Always cover the keypad when entering your PIN and don’t make it obvious which buttons you’re pressing.
"Take a look around you. If someone’s standing too close, get your card back without withdrawing any money and walk away.
"Your safety is the most important thing. Don’t approach anyone you think has been acting suspiciously and if you find loose parts on the machine don’t take them away with you."
Spot the signs - cash machine fraud
- You find a wobbly or bulky part that doesn’t seem to belong with the machine, such as a cover over the card slot or a loose keypad.
- Purchases and withdrawals start appearing on your account that you don’t remember making.
- Some cash machines are built entirely by fraudsters. Be cautious using a ‘standalone’ machine, rather than a ‘hole in the wall’, which is embedded in the front of a building such as a bank.
Anybody who notices suspicious devices around cash machines can report them to police on 101.