According to a Reuters report, Rep. Joe Barton -- the top Republican on the House Energy and Commerce Committee -- and George Radanovich -- the top Republican on the subcommittee on commerce, trade and consumer protection -- wrote JPMorgan Chase Bank CEO James Dimon on Wednesday.
The congressmen want to know how many customers were affected and how many were notified, the letter says.
"Breaches like this are of concern because of the variety of malicious crimes that can be perpetrated using stolen personal information," wrote Barton and Radanovich, who asked for a response to their questions by Oct. 31.
The bank, which declined Reuters' request on Thursday to say exactly when or where the incident occurred or how many customers were involved, did say it sent letters offering their customers "identity protection" for one year free of charge.
The letters reportedly notified customers that their Social Security numbers and addresses might have been on the missing backup computer tape, but that it contained no banking or financial information, a Chase spokesman said on Thursday.
The letters were sent out in August, according to the spokesman, who said the bank has received no indication that the information has been misused.
"You need special software to read the data," said bank spokesman Thomas Kelly, who declined to say how many people's information were on the tape.
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