Chinese foreign ministry spokesperson Mao Ning accused Thursday the United States of being a "hacker empire."

This came after Washington, its Western partners and Microsoft said state-sponsored Chinese hackers had infiltrated critical US infrastructure networks.

"But no change in tactics can alter the fact that the US is a hacker empire. I remember in September last year, relevant Chinese institutions released a report detailing the cyber attacks by the US National Security Agency on Northwestern Polytechnical University in China, the US should immediately address the relevant cyberattack activities, rather than deflecting by spreading disinformation," the foreign ministry spokesperson said.