LOUISVILLE, Ky. (WDRB) -- Getting gas for your car or money out of the bank seems harmless enough, but Metro Police are warning Louisville residents of a problem that has hit area gas pumps and ATMs.

It’s called "credit card skimming" and people in the Louisville area have fallen victim.

Not only does LMPD investigate these cases, but the Secret Service too, and on Friday we were given a look at some of the devices that have been used to steal money.

The skimmers are sometimes inserted inside the gas pump, where they aren’t easily detected.

A scammer somehow obtains a master key, then inserting the device.

“They just leave them in the pump and never come back,” said LMPD Sgt. Todd Brimm.

Other skimmers are placed around the pump and can access your information.

“They can actually hook them up to an IP address as well, and so they can access the device anywhere in the world,” Sgt. Brimm said.

The person responsible not only racks up your card information, but sometimes thousands and thousands of dollars on your dime.

Recently, a card skimmer was recovered from a Shelbyville gas station in March.

Someone first removed the card reader before re-inserting one that looked similar to the outside of the gas pump.

Other times, a device is also placed in front of the actual scanner, so that when you swipe your card you fall victim.

“Sometimes they use some type of device to leverage it in there or they’ve even velcroed them. So give it a tug. If it feels funny, don’t use it. If it feels like it’s loose, let someone know,” said Sgt. Brimm.

Sgt. Brimm says precautions are being taken at some gas pumps and ATMs, with more and more changing their locks and adding padlocks.

“It happens enough where we need to be aware of it,” says Sgt. Brimm.

He’s urging people to be careful, and choose a pump in direct access with a cashier. He says card skimming is something that LMPD and the Secret Service are looking out for.

“There’s ongoing investigations we can’t comment too much on, but it’s definitely something that makes you think of how you do your day to day operations,” said Sgt. Brimm.

Sergeant Brimm also recommends that people go inside to pay for their gas, or to get money out of the bank if possible, so that you don't have to rely on the outside pump or ATM.

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