In a matter of seconds, thieves can overlay a fake facade onto a gas pump or ATM machine in a scheme that can wipe out your bank account and generate tens of millions of dollars for crooks each month.

Criminals have kept up with safeguards such as encrypted chip technology that companies have implemented to protect debit and credit card users from fraud, FBI Special Agent Fred Bradford told Las Vegas businesspeople last week. In October alone, the Las Vegas police confiscated 23 “skimmers”—card readers—which probably saved merchants and banks some $46 million. Each skimmer can generate up to $2 million, and a single card can generate between $2,000 and $4,000.

Thieves learn how to build the skimmers on the Internet, the Las Vegas Sun reported. They particularly like to target older gas pumps, which are more vulnerable because they aren’t up-to-date on technological advances. Each time a consumer swipes a card, the information is saved and becomes available to the criminal. They can wirelessly reap the data via Bluetooth technology.

To avoid being ripped off, pay attention—facades sometimes obviously look fake. And it’s better to use a low-limit credit card than a debit card if you pay outside, since you won’t be revealing your PIN. Also, check your bank account daily to evaluate transactions, and don’t link debit cards to automatic payments. MORE INFORMATION