S Korea Hacked, Claims N Korea Stole Classified Military Info

North Korea is believed to have hacked into South Korea's cyber command, possibly obtaining classified information, Yonhap News Agency reported.

"It seems the intranet server of the cyber command has been contaminated with malware," an official with the Ministry of National Defense said. "We found that some military documents, including confidential information, have been hacked."

The cyber command said it did not yet know what data was breached, but said the affected server was isolated from the network to avoid spreading viruses throughout the system.

Though democratic South Korea has accused its communist neighbor of past cyber attacks, including stealing information from 10 South Korean officials' smartphones earlier this year, the current incident marks the first time the cyber command's data was compromised.

"The Ministry of National Defense assembled a joint investigation team, and after the investigation, we've confirmed that some military data, including confidential information, was leaked," Defense Ministry spokesman Moon Sang-gyun told reporters, per CNN. "North Korea is assumed to be behind this."

Rep. Kim Jin-pyo said the cyber command also was hacked in September, but no data appeared to be compromised in that attack.

But with the latest attack appearing to be successful at stealing classified information, South Korea is expected to rewrite its military operation plan, one source told Yonhap.

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