« USS McCain's top officers fired after 'preventable' deadly collision | Main | Catalan president claims mandate for independence but seeks dialogue with Spain first »

US-South Korean war plans reportedly stolen by North Korean hackers

iStock/Thinkstock(NEW YORK) -- Hackers in North Korea have allegedly stolen a cache of military documents from South Korea, according to a South Korean lawmaker.

Lee Cheol-hee, a member of South Korea's ruling Democratic Party, initially told local media outlets that the documents were taken in a September 2016 hack of the country's Defense Ministry. The ministry would not comment to ABC News, citing national security concerns.

"The way it got hacked was preposterous," Lee told ABC News, confirming what he initially told South Korean media. "It wasn't because North Koreans had advanced hacking skills but was due to negligence on the South Korean part."

He continued, "I don't think the situation is as serious as it may sound, but the reason why I alerted this is to push the new administration and the Defense Ministry to quickly find remedies so that this kind of loss don't happen again."

The sensitive documents also reportedly contained U.S.-South Korean plans for a "decapitation" strike against the North Korean regime, a plan that has supposedly angered North Korean dictator Kim Jong Un.

About 80 percent of the material stolen has not yet been identified. The stolen trove totals about 235 gigabytes, according to reports.

A Pentagon official told ABC News, “We don’t comment on intelligence matters.”

This hack was originally reported last May, but this is the first time details of what was stolen have emerged.

North Korea has been linked to other hacking attacks. The most notable was against Sony Pictures in 2014 as it was releasing "The Interview," a comedy about an assassination attempt on South Korea's Kim. More recently, the WannaCry ransomware attack targeted hospitals across the United Kingdom. North Korea has denied involvement in all of the attacks.

Copyright © 2017, ABC Radio. All rights reserved.

ABC News Radio