(Bloomberg) -- The fingerprint records of about 5.6 millioncurrent and former federal workers, contractors and job applicantswere stolen in the breach of the U.S. Office of Personnel Management’scomputer system, up from an initial estimate of 1.1million, the agency said Wednesday.

The breach is significant because fingerprints are increasinglybeing used by government agencies, corporations and consumers foraccess to computers, buildings and other devices.

“Federal experts believe that, as of now, the ability to misusefingerprint data is limited,” Samuel Schumach, a spokesman for OPM,which is the federal government’s jobs agency, said in a statement.“However, this probability could change over time as technologyevolves.”

U.S. officials and private cybersecurity experts believe the OPMbreach, which compromised data on 21.5 million individuals, wascarried out by the Chinese government.

The announcement Wednesday comes as Chinese President Xi Jinpingis in the U.S. and plans to hold a summit with President BarackObama on Friday. Cybersecurity is one of the top items that will bediscussed.

The announcement doesn’t increase the estimate that the hackcompromised sensitive information and Social Security numbers of21.5 million individuals, some of whom were screened for U.S. government securityclearances.

OPM said an interagency team will continue to analyze the dataas it prepares to mail notification letters to those impacted.

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