CNN  —  North Korea accused South Korea of flying propaganda-filled drones over Pyongyang and threatened “retaliation,” state media reported Friday. South Korea’s Joint Chief of Staff did not confirm or deny the accusations but urged North Korea to “not to act rashly” and said “all responsibility for the recent series of developments lies with North Korea,” referring to trash-laden balloons Pyongyang has been continuously sending to the South. On Friday evening, North Korea’s foreign ministry