A systematic effort by attackers to penetrate US government and industry computer networks stems most likely from the Chinese military, the head of a leading security institute claims.

The attacks had been traced to the Chinese province of Guangdong, and the techniques used made it appear unlikely it came from any other source than the military, said Alan Paller, the director of the SANS Institute, an education and research organisation focusing on cybersecurity.

"These attacks come from someone with intense discipline. No other organisation could do this if they were not a military organization," Paller said in a conference call on Monday to announced a new cybersecurity education program.