ARNOLD, Mo. — Arnold Police said they recently found skimmers at four of the pumps at an area Phillips 66, not installed on the card readers but hidden behind two security panels and hooked up to the circuitry inside the pumps.

"I actually had to research at what I was looking at," Det. Joshua Wineinger said.

They were alerted to the devices by a gas pump technician.

They say someone likely bought a cheap master key to make it through the first panel, then pried open the second layer with a screwdriver.

Every time a card was swiped, the device logged the card number, name, and expiration date.

Then that was all transmitted through a Bluetooth signal to the crooks.

"I feel like we're always one step behind," the detective said of advancing technology.

Wineinger said they expect there are now more skimmers in the area so the best thing you can do is to check that the security seal is intact before you fuel up.

Customers can also see if their phone picks up a Bluetooth signal with a long, random chain of numbers while near the gas nozzles. That could be a transmitter inside the pump.

Phillips 66 locations in Belleville and St. Louis have also found the new skimmers in their systems.

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