A Tired Mother and her Child
After the photographer snapped this photo at a funfair, the guide asked him to delete the photos. The guide was genuinely afraid that the photographer would post these and say that the mother was homeless. They didn't look homeless and most people would just assume it was a mother and child taking a breather, but the guides were extremely paranoid of how North Korea would be framed in the outside world.
Unknown Parasites
The South Korean government performed surgery on a North Korean defector when they found unknown parasites in his stomach. These parasites had never been seen in South Korea before, and they couldn't figure out if it was found in other parts of the world or not.