Police in Dorset are trying to trace people who have had their bank accounts accessed after having their card retained by a cash machine.
Two Co-Op cash machines in Corfe Mullen and six other machines in Bournemouth, Poole and East Dorset are believed to have been targeted by criminals.
Detectives think the machines were fitted with hidden cameras and devices which kept customers cards.
Two men have been charged in connection with the investigation.
The card capture devices are believed to have been fitted from mid-January to Co-op cash points in Wareham Road in Corfe Mullen, Station Road in West Moors, King John Avenue in Bear Cross, Columbia Road in Ensbury Park and Oakdale Road in Oakdale.
Det Sgt Richard Philp, of Dorset Police, said: "As is the case whenever a credit or debit card becomes trapped in a cash machine it is important that people call their bank right away.
"However, because banks often protect people against fraudulent cash withdrawals it's often the case that potential victims don't report suspicious activity to the police."
Detectives want to hear from anyone who had their bank card retained by the cash point machines at these locations and discovered fraudulent usage on their accounts in the last few weeks.