![North Korean leader Kim Jong-un.](/web/20170523043848im_/http://www.smh.com.au/content/dam/images/g/w/4/x/4/6/image.related.wideLandscape.460x259.gw9xas.png/1495410701809.jpg)
The North Korean cyber warfare cell that worries the West
North Korea's main spy agency has a special cell called Unit 180 that is likely to have launched some of its most daring and successful cyber attacks, according to defectors, officials and internet security experts.