Seoul, South Korea has asked China to help track the cyber attackers who briefly crippled the United States and South Korean governments earlier this year. A national police agency says they will seek help from Chinese authorities to launch a joint investigation to bring the offenders to justice.

The move comes after last week’s remarks by South Korea’s intelligence service chief Won Sei-Hoon, who blamed North Korea’s telecommunications ministry for the attacks. Won claims that their search into the route of the attacks on South Korean and US sites found a line coming from China.

Won says the line was found to be on the IP (Internet Protocol) that the North Korean Ministry of Post and Telecommunications is using on rent (from China). It was the first time the National Intelligence Service had named a specific body as the user of the IP address linked to the attacks. The intelligence agency also said that North Korea was a prime suspect in the “distributed denial of service” attacks designed to swamp selected websites with traffic.

The attackers infected thousands of “zombie” computers with a virus which programmed them to send a flood of requests for website access in July earlier this year. The origin of the attacks was never confirmed though, and one Vietnamese expert even cliamed they originated from a master server in Britain.

Information Technology experts say North Korea maintains elite hacker units. The threat of cyber warfare has prompted South Korea to establish a specific military command, which will be active in 2010.

Lieutenant General Jeffrey Remington of the US Air Force in South Korea has since called on Washington and Seoul to take “aggressive steps” to safeguard their military computer networks from increasingly sophisticated cyber attacks.