The Pentagon has admitted that the US military suffered the largest break in and theft of sensitive information as a result of hacking by a foreign government.
The US deputy secretary of defence William Lynn said that 24,000 files of data were stolen in an attach said to have taken place in March. "We have a pretty good idea who did it," Lynn said.
Lynn warned that it was nation states behind the most sophisticated attacks rather than rogue hacking groups. Some of the intrusions were said to have compromised sensitive systems including satellite communication and military hardware including missile tracking systems and drone aircraft.
Defence secretary Leon Panetta had earlier said that cybersecurity will be one of his main focuses as he takes over the top job in charge of the US military.
The DOD is planning to regard online as a branch of military in the same way as the navy, army and air force. The White House unveiled a proposal last month which would include enforcement of announcing data breaches and cyber-security audits for infrastructure providers.