John Kerry sends warning to Pyongyang

US Secretary of State John Kerry (C) speaks with South Korean President Park Geun-hye during a meeting at the Blue House in Seoul on February 13, 2014. Kerry arrived in Seoul on February 13 for discussions on North Korea's nuclear programme, a day after high-level inter-Korean talks failed to resolve a row over looming South Korea-US military drills. AFP PHOTO / POOL / Evan VucciEvan Vucci/AFP/Getty Images
US Secretary of State John Kerry (C) speaks with South Korean President Park Geun-hye during a meeting at the Blue House in Seoul on February 13, 2014. Kerry arrived in Seoul on February 13 for discussions on North Korea's nuclear programme, a day after high-level inter-Korean talks failed to resolve a row over looming South Korea-US military drills. AFP PHOTO / POOL / Evan VucciEvan Vucci/AFP/Getty Images

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    John Kerry sends warning to Pyongyang

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