Office of Personnel Management - 2014 data breach

In 2014 the U.S. Office of Personnel Management announced a data breach that exposed personnel records, including security-clearance background investigation data for millions of current and former federal employees. OPM later reported that the breach affected approximately 21.5 million individuals and included the theft of fingerprints for about 5.6 million. The U.S. government publicly attributed the breach to Chinese state-sponsored actors; that attribution has been debated by some observers.