South Korean soldiers from an artillery unit participate in a military drill near the demilitarised zone separating North Korea from the South, in Paju, north of Seoul March 29, 2013. North Korea put its missile units on standby on Friday to attack U.S. military bases in South Korea and the Pacific, after the United States flew two nuclear-capable stealth bombers over the Korean peninsula in a rare show of force. North Korean leader Kim Jong-un signed off on the order at a midnight meeting of top generals and "judged the time has come to settle accounts with the U.S. imperialists in view of the prevailing situation", the official KCNA news agency said. REUTERS/Lee Jae-Won