Thieves are using stolen payment cards to make small charges that could easily go unnoticed. The charges are attributed to generic-looking websites such as EEETsac.com, CEWcs.com and EduAcc.in, which claim to offer customer support services.

The Better Business Bureau, a consumer protection group, put out a national alert about the scam on Monday. The organization urged people to closely monitor past and current credit card statements and to call the actual card-issuing banks to resolve the issues.

It's not yet clear how widespread the fraud might be or how and when the affected credit card numbers were stolen. The Better Business Bureau and the nation's two major credit card companies, Visa and MasterCard, weren't immediately able to provide numbers.

The scam was first uncovered by cybersecurity journalist Brian Krebs, who found that it's part of a network of schemes stretching from Cyprus and India to the United Kingdom. He traced the operation to two men from Cyprus and a Malta-based bank that was processing the debit and credit card payments.

Some of the companies behind the fraudulent charges appear to be related, because they list phone numbers that are identical except for the last few digits.

When CNNMoney placed a call to those numbers, an operator explained that the $9.84 charge was for a "money-making online program" that came with access to videos and tutorials on how to work from home.

"If they really don't like online service, we will give them the full refund," the operator assured.

CNN