A state-sponsored Chinese hacking group has been spying on a wide range of U.S. critical infrastructure organizations, from telecommunications to transportation hubs, Western intelligence agencies and Microsoft (MSFT.O) said on Wednesday.
The espionage has also targeted the U.S. island territory of Guam, home to strategically important American military bases, Microsoft said in a report, adding that "mitigating this attack could be challenging."
While China and the United States routinely spy on each other, analysts say this is one of the largest known Chinese cyber-espionage campaigns against American critical infrastructure.
The Chinese embassy in Washington did not immediately respond to a Reuters request for comment.
It was not immediately clear how many organizations were affected, but the U.S. National Security Agency (NSA) said it was working with partners including Canada, New Zealand, Australia, and the UK, as well as the U.S. Federal Bureau of Investigation to identify breaches. Canada, UK, Australia and New Zealand warned they could be targeted by the hackers too.
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