Secret Service Investigating Target Credit Card Breach

(Undated) -- The Secret Service is investigating a security breach at Target stores involving millions of in-store credit card records. The investigation comes as a report by respected computer security expert Brian Krebs says the breach occurred around Black Friday, one of the busiest shopping days of the year. The theft involves the data stored on the magnetic strip of cards used at Target stores nationwide. The breach does not affect online transactions. The report said both credit and debit card users are affected by the breach.