Alan Paller, the director of the SANS Institute, claims that the Chinese military is trying to penetrate US government and industry computer networks through cyber attacks.
He said that the hackers used techniques that showed intense discipline which is rare in hackers normally which makes it unlikely that they came from anywhere but the military.
The attacks were clean leaving no fingerprints or keystroke errors, he said, and included creating a backdoor in less than 30 minutes. Among the things stolen during the attacks are the US military flight planning software from Redstone Arsenal. Source