Three men have been arrested on suspicion of targeting cash machines in Derby with skimming devices.
The alarm was raised after a person reported a machine at the Co-op in Allenton had been tampered with.
Police were then alerted to a group of men acting suspiciously and arrested the three, aged 21, 25 and 26, in Normanton Road.
Skimming involves attaching devices to cash machines to take money before it can reach the external cash tray.
The men were arrested on suspicion of theft.
They have been interviewed and bailed pending further inquiries.