The Office of Personnel Management said Wednesday that 5.6 million individuals' fingerprints were stolen in the massive breach the agency discovered earlier this year -- more than five times the amount originally reported.
OPM, which screens and hires federal workers, had previously said 1.1 million people's fingerprints had been compromised. "[T]he ability to misuse fingerprint data is limited. However, this probability could change over time as technology evolves," OPM warned in an alert on Wednesday.
The huge increase in the stolen-fingerprint figure -- which OPM revised as part of its continuing investigation -- doesn't change the agency's overall estimate of 21.5 million individuals affected by the breach.
OPM first revealed on June 4 that it had discovered a cyberattack that compromised data for at least 4.2 million current and former federal employees. On June 12 OPM disclosed a second attack that targeted information for millions more Americans who applied for security clearances. U.S. officials identified China as the culprit, a charge Chinese officials vehemently denied. OPM director Katherine Archuleta stepped down from her post in the aftermath of the breach.
The agency said Wednesday it is working with groups including the Federal Bureau of Investigation, the Department of Homeland Security, the Department of Defense and others to determine the potential misuse of the stolen data. OPM also reiterated that it is "working to begin mailing notifications" to people whose data was compromised, sent on a rolling basis.