LOUISVILLE, Ky. (WDRB) -- Louisville Metro Police say they've arrested a Fairdale man who tried to sell an undercover detective 200 credit card numbers stolen through the use of gas pump skimmers.

According to an arrest report, it happened last night.

Police were tipped off that 32-year-old Leonardo Rodriguez was selling stolen credit card numbers, so an undercover detective contacted him in an effort to set up an exchange. Police say Rodriguez agreed to sell the detective 200 stolen credit card numbers for $4,000. Rodriguez allegedly told the detective that he would provide a USB drive containing the numbers, which could then be re-encoded onto blank cards and used as a form of payment.

When the detective arrived at the pre-arranged location, the detective saw Rodriguez with a laptop. 

Rodriguez was arrested. Police say he allowed officers to search him -- and at that point the detective found multiple keys used exclusively to gain access to gas pumps.

"It is necessary for individuals involved in this scheme to gain access into the gas pumps to plant the skimmer to unlawfully collect and intercept financial information," the arrest report states.

Police say they seized three USB drives, along with the laptop, from the vehicle.

After executing a search warrant on the USB drives, police say they found approximately 300 stolen debit and credit card numbers, along with the names of the victims. Upon examining the laptop, police say they found card writing software used to re-encode the blank cards.

"The presence of the large number of stolen credit card numbers, the keys used to unlawfully gain access into the gas pumps, his agreement to sell [the detective] the large number of stolen credit / debit cards is indicative of trafficking in financial information," the arrest report states.

Police say Rodriguez was already on felony diversion for similar charges in the past.

He was charged with 300 counts of trafficking in financial information and one count of possession of burglary tools.

"It's a nationwide problem that's going on across the country. In fact, this individual used it other places around the state of Kentucky as well as other states," said Dwight Mitchell, LMPD spokesperson.

So, gas stations have taken measures to protect themselves.

"In our case we have custom locks on every pump at every store, verses the default lock that comes on the pump when you buy it from the manufacturer. So, if the retailer doesn't choose to change that out, those keys, I think, can even be bought on the Internet. Fortunately, we haven't experienced it but at the same time we've spent over a million dollars to protect our pumps from this type of activity," said Tony Harris, Thorntons President.

But not all gas stations haven taken such measures and most people don't even know they're at risk.

"That's not good, I wouldn't think twice about it. I don't know if there's much you can do to stop it," said Rob Panther, a customer pumping gas.

Police say there are measures you can take to prevent credit card fraud.

"When you use your credit card, particularly on gas pumps, that's probably not the thing to do. You may want to go in and pay with cash or if you must use your credit card or debit card go inside the gas station location," said Mitchell.

If you believe a credit card reader has been tampered with officials ask for you to tell the gas station employee and inform authorities.

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