WASHINGTON — Chinese hackers in March broke into the computer networks of the US government agency that houses the personal information of all federal employees, senior US officials said. They appeared to be targeting the files on tens of thousands of employees who have applied for top-secret security clearances.
The hackers gained access to some of the databases of the Office of Personnel Management before the federal authorities detected the threat and blocked them from the network, the officials said. It is not yet clear how far the hackers penetrated the agency’s systems, in which applicants for security clearances list their foreign contacts, previous jobs, and personal information, like past drug use.
In response to questions about the matter, a senior Department of Homeland Security official confirmed that the attack had occurred but said that, “at this time,” neither the personnel agency nor Homeland Security had “identified any loss of personally identifiable information.” The official said an emergency response team had been assigned “to assess and mitigate any risks identified.”
One senior US official said that the attack was traced to China, although it was not clear whether the hackers were part of the government.
Just a month ago, the Justice Department indicted a group of Chinese hackers who work for the People’s Liberation Army Unit 61398 and charged them with stealing corporate secrets. The same unit, and others linked to the PLA, have been accused in past intrusions into US government computer systems, including in the office of the secretary of defense.