LOUISVILLE, Ky. (WDRB) -- When you're pumping gas or hitting up the ATM for cash, criminals may be taking advantage of you. The U.S. Secret Service is warning the public about an ongoing problem that has gotten worse.

Hidden skimming devices taking your card information.

"Skimming is a kind of a slang word that law enforcement community uses," explained Acting Special Agent in charge of the Louisville Field Office for the Secret Service.

Criminals use devices to steal your card's information, then make new, fake cards they can sell.

"Over a weekend you might get 1,000 card numbers and if you can sell them for even $5 a card on the black market, you're way ahead of what you spent to purchase this (skimming) equipment," said Hutzell.

It's placed there fast and often at night.

"They simply pull up and place it right over the ATM itself," Hutzell explained while showing an ATM skimming device.

Gas pumps are accessed by criminals quickly, often using a universal key.

"Some gas stations have a universal key amongst their brand and if somebody gets a copy of that universal key, then they can simply open the pump up and get access to the necessary wires they need," said Hutzell. "These devices can be connected and up and working with in 30 seconds."

Hutzell says criminals will install the skimming devices at night with a large vehicle blocking view, so they are not detected.

The Secret Service is asking businesses to inspect ATMs and gas pumps daily. They suggest gas stations use a sticker on the panel. If the seal has been broken, it is likely someone has been inside the panel, tampering.

It is a growing problem. Two men were arraigned Wednesday on charges related to skimming. Police say they were caught using more than 100 fake cards. Officials say they found equipment the men used to make the cards.

The Secret Service is focusing its investigation in Nelson County where several banks and gas stations have been hit. That includes some ATMs at two Town and Country Banks in Bardstown.

Hutzell says there is not much consumers can do to protect themselves. But another warning does come with advice. Some devices have cameras that can record you punching in your PIN. Hutzell says be cautious: "Cover their fingers as they're doing that. That prevents the camera from picking up the PIN."

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