North defectors literally put their lives in danger when making their journey out of the North. Getting caught means death either by execution or getting dragged into concentration camps.
In fact, North defectors have been repatriated to their homeland by the Chinese government which is a chronic problem. Concerned citizens of the South rallied together when the Chinese government decided to deport North defectors back on March 15. Citizens around the world have rallied together to stop the government, but the result is dubious.