Chinese Suspected in Huge Data Hack

Described as one of the largest thefts of government data ever seen.

U.S. officials suspect that hackers in China stole the personal records of as many as four million people in one of the most far-reaching breaches of government computers.

The Federal Bureau of Investigation is probing the breach, detected in April at the Office of Personnel Management. The agency essentially functions as the federal government’s human resources department, managing background checks, pension payments and job training across dozens of federal agencies.

Investigators suspect that hackers based in China are responsible for the attack, though the probe is continuing, according to people familiar with the matter. On Thursday, several U.S. officials described the breach as among the largest known thefts of government data in history.

It isn’t clear exactly what was stolen in the hack attack, but officials said the information can be used to facilitate identity theft or fraud. The Department of Homeland Security said it “concluded at the beginning of May” that the records had been taken.

At a Chinese Foreign Ministry briefing on Friday, ministry spokesman Hong Lei said, “Cyberattacks are anonymous, cross-border and hard to trace. If you keep using the words “maybe” or “perhaps” without making a thorough study, this is irresponsible and unscientific.” He said China opposes all forms of cyberattacks. “We hope the U.S. side will shed its suspicions.”

In response to previous allegations of Chinese hacking and cyber-espionage, Beijing has said that China is also a target of hacking attacks from overseas.

China and the U.S. have sparred over cybersecurity, with the U.S. accusing Chinese government military officers of sustained hacking of U.S. firms for economic advantage. Chinese authorities have denied those accusations.

Investigators believe the attack is separate from a hacking incident detected last year at the Office of Personnel Management. That attack was far smaller, although officials didn’t disclose at the time how many employees were affected. In another apparently unrelated computer attack, Russian hackers are suspected in a large, long-running breach of State Department computers.

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