WASHINGTON—Hackers stole Social Security numbers from more than 21 million people and snatched other sensitive information in a recent breach of U.S. government computer systems, the Obama administration said Thursday.
The U.S. Office of Personnel Management said Thursday that more than 19 million who applied for background investigations had their information compromised, as well as nearly 2 million of their family members — like spouses or cohabitants — who never applied for a background check.
