North Korea insisted on Sunday that it is not using an American, who has been sentenced to 15 years in a hard labor camp on murky charges, as a bargaining chip to get leverage in talks with the U.S. Kenneth Bae, a South Korean by birth who became a naturalized American citizen, was found guilty of crimes against the state, although his exact crime is still unclear. The U.S. State Department urged North Korea to release Bae and give him amnesty, but an official in Washington said last week that there are no plans to send an envoy to negotiate Bae’s release.