WASHINGTON, D.C. ? As many as 38,000 veterans may be at risk of identity theft because a Veterans Affairs Department subcontractor lost a desktop computer containing their sensitive personal data.

VA Secretary Jim Nicholson said that Unisys Corp., a subcontractor hired to assist in insurance collections for VA medical centers in Philadelphia and Pittsburgh, reported the missing computer last Thursday. The computer was being used in Unisys offices in Reston, Va.

It is not yet known what happened to the computer, Nicholson said, adding that local and federal authorities are investigating.

The computer is believed to contain names, addresses, Social Security numbers, dates of birth, insurance carriers and claims data including medical information for veterans who received care at the hospitals in Philadelphia and Pittsburgh during the past four years.