North Korea doubles its cyber warfare team to 6,000 troops

North Korea has doubled the number of personnel in its cyber warfare divisions, can deploy more armoured vehicles, rocket launchers and warships and is developing a new generation of miniature submarines designed to land saboteurs, according to South Korea's defence white paper.

Seoul's assessments of Pyongyang's conventional military and "cyber army" capabilities were released on Tuesday. The report also concluded that North Korea has achieved a "significant level" of the technology needed to miniaturise nuclear warheads in order to mount them on ballistic missiles.

Pyongyang continues to strenuously deny any involvement in the hacking attack against Sony Pictures Entertainment, apparently in retaliation for the slapstick comedy "The Interview", although South Korean intelligence understands that the North now has 6,000 skilled cyber-warfare experts.

Read more