SEOUL, South Korea -- North Korean leader Kim Jong Un has vowed to shut down the country's nuclear test site in May and open the process to experts and journalists from South Korea and the United States, Seoul's presidential office said Sunday. 

With a single step over a weathered, cracked slab of concrete, North Korean leader Kim Jong Un made history Friday by crossing over the world's most heavily armed border to greet South Korean President Moon Jae-in for talks on North Korea's nuclear weapons