02:52 - Source: CNN
How the reported Chinese hackers worked

Story highlights

Mandiant say thousands of cyber attacks have come from one neighborhood near Shanghai

The espionage group mainly targeted U.S. blue chip companies in 20 separate industries

Mandiant VP Grady Summers says diplomatic pressure is needed on Beijng from Washington

The Chinese government is sponsoring cyber-espionage to attack top U.S. companies, according to Grady Summers, vice president of security firm Mandiant.

Virginia-based Mandiant published a 60-page report detailing allegations over a six-year period against a group of hackers – known as Comment Crew – which Summers linked to a secret division of the Chinese military.

Summers told CNN: “China is attacking the U.S. on a scale like we’ve never seen before… We believe that the Communist Party of China is very aware of this.”

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Mandiant says the activity can be traced to four networks near Shanghai – with some operations taking place in a location that is also the headquarters of Unit 61398, the secret military division.