South Korea's cyber command established to counter external hacking attempts on the country's military was found to have been hacked last month, a lawmaker said Saturday, raising speculation that North Korea might be behind the latest cyber attack.

Rep. Kim Jin-pyo, a lawmaker of the main opposition Minjoo Party of Korea, told Yonhap News Agency in a telephone interview that the hacking targeted the "vaccine routing server" installed at the cyber command.

Kim is a member of the parliament's national defense committee.

"A malicious code has been identified and it seems to have taken advantage of the vulnerability of the routing server," he said. "In a cautious measure, the server has been separated from the network."

The server is tasked with security on computers that military has for Internet-connection purpose. Around 20,000 military computers are known to have been connected to the server.

Kim said that chances are "very low" that the latest hacking led to a leak of confidential information given that the military's intranet is not connected to the server.

An investigation is underway to figure out where the hacking originated. He said that it has yet to be confirmed whether the North was involved but noted that military authorities are leaving that possibility on the table. (Yonhap)