Chinese Army Unit Is Seen as Tied to Hacking Against U.S.

WASHINGTON , When the Obama administration circulated to the nation’s Internet providers last week a lengthy confidential list of computer addresses linked to a hacking group that has stolen terabytes of data from American corporations, it left out one crucial fact: that nearly every one of the digital addresses could be traced to the neighborhood in Shanghai that is headquarters to the Chinese military’s cybercommand.

In the next few months, American officials say, there will be many private warnings delivered by Washington to Chinese leaders, including Xi Jinping, who will soon assume China’s presidency.

Officials at the Chinese embassy in Washington again insisted that their government does not engage in computer hacking, and that such activity is illegal. They describe China itself as a victim of computer hacking, and point out, accurately, that there are many hacking groups inside the United States. But in recent years the Chinese attacks have grown significantly, security researchers say. Mandiant has detected more than 140 Comment Crew intrusions since 2006. American intelligence agencies and private security firms that track many of the 20 or so other Chinese groups every day say those groups appear to be contractors with links to the unit.