NATICK, Mass. (AP) – BJ’s Wholesale Club has tightened computer security after finding that credit card information of hundreds of customers may have been stolen from the company.

BJ’s released a statement late Friday saying that “a small fraction” of its eight million members may have had credit card information stolen. The Boston Herald reported that credit card companies told BJ’s that a few hundred customers may have had their information stolen.

BJ’s, in a statement, said it took immediate steps to address the theft, including conducting a review of its technology systems with a computer security firm.

After the review, BJ’s ruled out the likelihood of a hacker attack on its central computer system, and put into place measures on the club level to close off potential ways to steal credit card information.

“We take this issue very seriously and we are continually working to employ advanced technologies to ward against increasingly sophisticated credit card information theft schemes,” said Bob Hamilton, BJ’s vice president of Loss Prevention.

BJ’s operates 150 clubs, one of them in Auburn, and 78 gas stations.