______ MasterCard users are NOT affected by the recent security breach. [origina

A senior executive of MasterCard on Monday said the company’s Chinese mainland users are not affected by the recent security breach, during which millions of credit card users may have had their information stolen by a computer virus.
   In a statement, MasterCard said the data centers involved in the accident were not involved with transactions of mainland users.
   In addition, the stolen information only contains card numbers and expiration dates, but not any other data like personal identity or birthdays.
   Another international credit card organization, Visa, also made an announcement yesterday, saying they are going over mainland users’ information, and will inform domestic banks after the work is finished.
   Meanwhile, domestic lenders said basic information from their credit cards are stored in mainland banks, although many of the cards are issued jointly with MasterCard and Visa.