US nuclear envoy wraps up surprise N. Korea visit

US envoy Christopher Hill was wrapping up a surprise trip to North Korea on Friday, amid optimism that the visit heralds renewed progress in international efforts to denuclearize the communist country. Hill, an assistant secretary of state, arrived in Pyongyang on Thursday in the highest-level US visit to the North Korean capital since 2002. Hill is Washington's chief envoy to international talks on North Korea's nuclear program. He was to meet his North Korean counterpart Kim Kye Gwan and, possibly, other officials during the landmark visit, which came amid hopes North Korea was on the verge of taking concrete steps to carry out its commitment to shut down its bomb-making nuclear reactor.