MADISON, Wis. (10/14/10)--A data breach at Aldi’s grocery stores as a result of tampered debit card payment terminals at some stores has affected many financial institutions, including at least one credit union. ESL FCU, a $3.74 billion-asset credit union based in Rochester, N.Y., shut off 3,700 member debit cards Saturday to prevent infiltration of accounts, said ESL spokeswoman Francine Patella Ryan (Democrat & Chronicle Oct. 13). The credit union has been reviewing account activity for unusual transactions, the newspaper added. The breach has occurred in at least 11 states, according to Aldi’s website, but could be even more widespread. Aldi said its machines were tampered with between June 1 and Aug. 31 (Examiner.com Oct. 2). Roughly 200 people notified authorities that unauthorized withdrawals ranging from $100 to $900 were taken from their accounts, the Chicago Tribune reported (via Examiner.com). Aldi operates more than 1,100 U.S. stores in 31 states from Kansas to the East Coast.