TODAY | December 19, 2013
>> risk on those cards.
>> i can't imagine any good time for this, at the height of the holiday season , it couldn't come at a worst time.
>> the theft of payment card information at target, one of the nation's largest retailers. it apparently went on for weeks and was only just detected. cnbc's mary thompson has been looking into this. mary, talk to me about where the breach occurred. is there an online element to this as well.
>> customers who use their debit and credit cards , it doesn't impact online shoppers. target says the breach took place starting plaque friday. which you mentioned "busiest shopping day of the year, all the way through last sunday, december 15th . they said they take this matter very seriously to bring those responsible to justice. target is working with a 3rd party forensics firm.
>> i was going to ask you how extensive it is. by target's own statement, approximately 40 million credit and debit cards may have been impacted between those dates. target alerted the authorities and financial institutions immediately. do we know exactly what kind of information may have been culled from those cards?
>> what the thieves were after is the data on the magnetic strip on the back of the data or debit card . they can put it on counterfeit cards. the fed can access the account.
>> secret service involved in that