The Amnokggang crew, in Pyongyang. Jenkins taught up there before defecting to Japan. They turn out some smart kids. I would suspect KIS University is also involved, too.
They can manufacture articles and comments under different name all day and all night, while bumping up or raising scores for articles favorable to their interest.
These people are responsible for significant portion of Internet traffic on political issues.
All of them could go away overnight if NK regime collapses. That will be the moment when we can accurately measure the true extent of their Internet presence. Hope that day would be coming soon.