Chinese Cyber Hackers Are Back in Business

Private security firm Mandiant says publicity hasn't stopped Unit 61398's attacks.

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A team of Chinese cyber hackers allegedly responsible for stealing hundreds of terabytes of blueprints, pricing documents and other information from organizations within the U.S. is back in business, according to the private security firm that first unveiled the military group's activities.

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Unit 61398, which operates out of a 12-story building in Shanghai, has restarted its clandestine online attacks against private firms and government organizations, three months after its identity was first exposed by Mandiant. The security company, which helps guard organizations from these attacks, has not specified the latest targets, reports The New York Times.

Mandiant first exposed the unit in mid-February detailing the group it called "APT1," which had broken into the networks of 141 companies, spanning 20 major industries. The White House believed a campaign of publicizing the unit's activities might force it to cease its hacking efforts, but the Times cites American officials and security companies who say it has resumed the attacks at roughly 70 percent of its original capacity.

Unit 61398 employs roughly 1,000 people, according to the Mandiant report, and is alleged to have stolen technology blueprints, proprietary manufacturing processes, test results and business plans. The report also says the group's activities are likely government sponsored.

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The Chinese Foreign Ministry denounced these claims as "groundless," and the Defense Ministry denied any connection with the unit.

An expert in cyber attacks told U.S. News in February that the extent of the attacks is likely diluted because of its secretive classification.

"I don't think the report comes close to quantifying the problem—it's all based on unclassified information. To have any idea, we'd have to know the classified portion of this," said Kevin Coleman, a senior fellow with the Technolytics Institute. "I think if you take what information is covered publicly and multiply it by five, that's how bad it is."

The most recent cyber hacks began shortly after Chinese officials told U.S. Secretary of State John Kerry that they would be willing to begin discussions on cyber security with the U.S., reports the Voice of America.