From Nothing to Envy: Ordinary Lives in North Korea, by Barbara Demick (Spiegel & Grau, 2009), Kindle Loc. 2613-2626:
It is worth noting here how extraordinary it was for anyone to be homeless in North Korea. This was, after all, the country that had developed the most painstaking systems to keep track of its citizens. Everybody had a fixed address and a work unit and both were tied to food rations—if you left home, you couldn’t get fed. People didn’t dare visit a relative in the next town without a travel permit. Even overnight visitors were supposed to be registered with the inminban, which in turn had to report to the police the name, gender, registration number, travel permit number, and the purpose of the visit. Police conducted regular spot checks around midnight to make sure nobody had unauthorized visitors. One had to carry at all times a “citizen’s certificate,” a twelve-page passport-size booklet that contained a wealth of information about the bearer. It was modeled on the old Soviet ID.
All that changed with the famine. Without food distribution, there was no reason to stay at your fixed address. If sitting still meant you starved to death, no threat the regime levied could keep people home. For the first time, North Koreans were wandering around their own country with impunity. Among the homeless population, a disproportionate number were children or teenagers. In some cases, their parents had gone off in search of jobs or food. But there was another, even stranger, explanation. Facing a food shortage, many North Korean families conducted a brutal triage of their own households—they denied themselves and often elderly grandparents food in order to keep the younger generation alive. That strategy produced an unusual number of orphans, as the children were often the last ones left of entire families that had perished.