The real MasterCard data security story

The Irish Independent also reports that credit card giant MasterCard has sought to play down what has been called the biggest ever security breach which exposed more than 40 million cards to possible fraud.

MasterCard, which had 14 million of its credit cards accounts exposed to possible fraud, said only a small fraction of them were considered "at high risk".

But mystery still surrounds the nature of the security breach, and there is controversy over MasterCard's decision to go public about it.

MasterCard announced on Friday that the breach was traced to Atlanta-based CardSystems Solutions In, which processes credit card and other payments for banks and merchants.

CardSystems' chief financial officer, Michael A Brady, said his company was "blindsided" by the MasterCard release, adding that his company was told by the FBI not to release any information to the public. FBI spokeswoman Deb McCarley said they did ask CardSystems to not release details that might compromise the investigation - but denied asking the company not to disclose that the intrusion occurred.

"I'm not sure where they got that impression. It's important for the public to be warned so card holders can be more careful while checking their statements." But she declined to confirm reports that the breach was the result of internet hacking.

"I'm not going to get into details of what we have been able to determine right now," she said.

MasterCard spokeswoman Jessica Antle said only about 68,000 of its card holders are at "higher levels of risk", and should closely examine their credit or debit card accounts. Customers do not have to worry about identity theft, Antle said. "No, none at all," Antle said. "Social Security numbers, dates of birth, information like that are not stored on your credit card."

The incident appears to be the largest in a series of security breaches affecting valuable consumer data at major financial institutions and data brokers.

A few weeks ago, Citibank said it had lost the personal data on almost four million customers after delivery service UPS lost a box of tapes.