South Korean military accuses North of cyber warfare

"North Korea is trying to steal military secrets and cripple our defence information system by using experts specially trained to hack into our military information network," said Defence Security Commander Bae Deuk-Shik, at a security forum. 

He said the North has tried to "stir up social disorder by paralysing our core infrastructure through cyber terror as it can cause enormous damage in a short period."

Korea University Professor Lee Dong-Hun also told the security forum that North Korea had set up a special unit of 3,000 elite hackers under the direct control of new leader Kim Jong-Un. "North Korea is the world's third most powerful nation in cyber warfare after Russia and the United States," said Professor Lee.