"They're everywhere," Hoglund said of Chinese intrusion attempts. "Malware that looks like kids have written it is being used to steal weapons plans."
There is also some doubt about the evidence, according to some analysts.
Discrepancies in published reports about the attack and the risks existing at the time don't always match up, according to one analysis.
Given the bulk of circumstantial evidence, the prototypical method of the attack and China's track record in both intellectual property theft and cyberespionage, there is little doubt that it was behind the attack, Congressman Rogers told Reuters.
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