Estimate of Americans hit by government personnel data hack skyrockets

By Patricia Zengerle and Megan Cassella WASHINGTON (Reuters) - Data breaches at the U.S. government's personnel management agency by hackers, with suspicions centering on China, involved millions more people than previously estimated, U.S. officials said on Thursday. The Office of Personnel Management (OPM) said the stolen data included Social Security numbers and other sensitive information on 21.5 million people who have undergone background checks for security clearances.