South Korean vehicles head for NK city of Kaesong amid rising tension between the two sides

South Korean army soldiers walk as vehicles wait to head to the North Korean city of Kaesong at the customs, immigration and quarantine office in Paju, South Korea, near the border village of Panmunjom, Monday, April 1, 2013. North Korea warned South Korea on Saturday that the Korean Peninsula had entered “a state of war” and threatened to shut down a border factory complex that’s the last major symbol of inter-Korean cooperation. <AP Photo/NEWSis/Ahn Young-joon>