China is no stranger to hacking allegations, but now the Pentagon says it has hard proof that China has been engaging in cyber espionage.
China's government has been snooping to get information about the US government and military, according to a Pentagon report released on Tuesday.
"In 2012, numerous computer systems around the world, including those owned by the US government, continued to be targeted for intrusions, some of which appear to be attributable directly to the Chinese government and military," the report said.
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Chinese officials have denied the allegations. "This is not beneficial to US-China mutual trust and cooperation," Chinese Foreign Ministry spokeswoman Hua Chunying told reporters.
She also denied the hacking allegations. "We firmly oppose any groundless criticism and hype, because groundless hype and criticism will only harm bilateral efforts at cooperation and dialogue."
According to Agence-France Presse, the report is the "most explicit statement" from the United States accusing China of cyber-espionage.
In February, US cyber security firm Mandiant linked hundreds of data breaches to a Chinese hacking team traced to a military unit, BBC News reported.