Visitors pass by weapons at Korea War Memorial Museum as tensions escalate between the two Koreas

Visitors pass by weapons deployed in the Korean War era at Korea War Memorial Museum in Seoul, South Korea, Sunday, April 7, 2013. South Korea’s top security official said Sunday that North Korea may be setting the stage for a missile test or another provocative act with its warning that it soon will be unable to guarantee diplomats’ safety in Pyongyang. But he added that the North’s clearest objective is to extract concessions from Washington and Seoul. <AP Photo/Ahn Young-joon>

A man hangs a ribbon to a wire fence covered with ribbons carrying messages visitors left to make their wishes for the reunification of the two Koreas, at the Imjingak Pavilion near the border village of Panmunjom, which has separated the two Koreas since the Korean War, in Paju, north of Seoul, South Korea, Sunday, April 7, 2013. <AP Photo/Lee Jin-man>