The public have been warned against using Santander cash machines over fears they have been "compromised" by criminals.
Police in Lancashire and Cheshire say they have been notified of issues with the bank's ATMs. It follows reports of suspicious devices on the bank's machines across the country last week.
Officers are concerned that criminals have targeted the machines in an attempt to steal card details and cash, and urged those who have lost money to contact the bank, the Press Association reported.
A police spokesman said it feared the issue could be more widespread and warned the public to be "vigilant, in particular of Santander machines, but of any cash machines".
The spokesman added: "Report anything suspicious, have a visual check of the cashpoint and if in doubt leave it and go somewhere else.
“It’s spread across the whole of Lancashire so it’s highly likely other forces may have had reports. We do not know how many are affected.”
The force advised members of the public to not use cash machines if they appear to be tampered with and to shied the keypad when entering pin numbers.
Cheshire police also issued a warning to avoid Santander machines in Wilmslow, near Manchester.
The force tweeted: “Cheshire police have received reports of issues with Santander ATM’s in Wilmslow. Please do not use the machines and call your bank and 101.”