Washington: North Koreans are raised to be soldiers and "have no ounce of freedom", according to a journalist who lived undercover in Pyongyang. "Their lives were completely mapped out according to the great leader," Suki Kim, who spent six months undercover in North Korea in 2011, told CNN on Saturday. "Any information from outside is forbidden and not shown to them in any way. It's really a system of absolute control." Kim, author of "Without You There Is No Us", posed as a missionary and a teacher at Pyongyang University of Science and Technology. She taught English to the sons of North Korea's ruling class, children expected to be the regime's future leaders. She described the complex psychology of people there "being really lovely and absolutely human" but living in a bubble, emotionally and intellectually isolated. "To try to understand North Korea, it's basically a cult of the great leader," Kim told CNN. "It's a military dictatorship with one of the largest armies in the world and also it's a place where communication is blocked. "If you block the rest of the world from your country entirely, then how can you actually have information to teach people that other things exist?" Kim said computer majors in the university did not even know about the existence of the internet. Her students had to attend weekly meetings to report on each other, "so there's a surveillance system". "There's a building that exists for studying the great leader. You go and study the great leader and you also guard that building. You clean that building," she said. According to Kim, citizens have access to only one newspaper and one television station dedicated to teaching them about their leader. "They (the citizens) don't travel inside or outside of their country, giving them little time or access to think about anything else but their leader and therefore conditioning them. "The country is nothing like we've seen before. It's a nuclear power that is also absolutely enslaving its citizens for the sake of this really one-man nation." "It's the saddest place in the world," Kim added.