WASHINGTON (CNN)  -- The National Archives -- a repository of important government documents, including the U.S. Constitution -- has lost a computer hard drive containing large volumes of Clinton administration records, including the names, phone numbers and Social Security numbers of White House staff members and visitors. The National Archives has lost a hard drive containing large volumes of Clinton administration records. Officials at the Archives say they don't know how many confidential records are on the hard drive. But congressional aides briefed on the matter say it contains "more than 100,000" Social Security numbers, including one belonging to a daughter of then-Vice President Al Gore. It also contains Secret Service and White House operating procedures, the staffers said they were told.
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Officials say they don't know how many confidential records are on the hard drive
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Congressional aides say "more than 100,000" Social Security numbers on drive
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Archives announced a $50,000 reward for information leading to its return
The @placeholder also said it has taken steps to improve security, including both physical control of records and the treatment of personal information.