An American citizen who has been sentenced to 15 years of hard labor in North Korea began his sentence Tuesday at a “special prison,” state media reported. Making matters even more bleak: two South Korean experts told the Associated Press that they didn’t even know what a “special prison” was. Kenneth Bae, a South Korean by birth who has become a naturalized U.S. citizen, has been accused by Pyongyang of trying to create an anti-government base in the North, although outside analysts have speculated that Bae could be used as a bargaining chip in diplomatic negotiations with Washington. A North Korean academic told the Associated Press that Bae had been told that he couldn’t appeal his sentence, and he should instead urge Washington to push for amnesty. There has been no indication that Washington will send any high-profile envoys to negotiate for Bae.