With help from US Secret Service agents, Stop & Shop Supermarket Cos. executives scrambled yesterday to determine how many consumers may have had their credit and debit card data stolen by high-tech thieves who apparently broke into checkout-line card readers and planted the equivalent of bugs to steal information.

Stop & Shop said customer information, including personal identification codes for cards, was confirmed stolen from supermarkets in Coventry and Cranston, R.I. The company said it had found evidence that card readers were tampered with in a similar way at four other stores in Seekonk and in Bristol, Providence, and Warwick, R.I. But the supermarket company said it had no reports of illegal transactions on cards that had been used at those stores.

http://www.boston.com/business/globe/articles/2007/02/19/stop__shop_reports_credit_data_was_stolen/