The graffiti, found June 24th on a wall at Pyongyang Railroad College reportedly called Kim Jong Il "a dictator who starved people to death." Not exactly Banksy, but it gets the point across.
The easiest thing would have been to erase the graffiti, then maybe demolish the wall for traitorous behavior. But instead, authorities launched a three-day investigation, cutting off the city and erecting checkpoints for all passersby.
NK Daily talked to a Chinese trader about the investigation:
According to the trader, the authorities launched the search for the person responsible via a joint investigation team including the National Security Agency and People's Safety Ministry, specifically targeting students and people from other provinces. They established road blocks on the roads linking Pyongyang Station and West Pyongyang Station, Pyongyang-Pyongsung, Pyongyang-Wonsan and Pyongyang-Kanri, then began questioning all passers' by.
Reporting the latest, he said, "The investigation unit has now narrowed down the investigation to the Railroad College's own students, and has blocked the movement of people between provinces in order to stop the spread of rumors. It seems they are dealing with it severely since it happened in Pyongyang not in the provinces."
You hear that, American street artists? You guys have it easy. Go tag Pyongyang. Dare you.