Would a nuclear meltdown inside North Korea be deadlier than the 1986 Chernobyl disaster? That question has set South Korea abuzz after President Park Geun-hye this week warned of the potentially devastating impact of an accident in the North.

Speaking in The Hague at the Nuclear Security Summit, Ms. Park said Monday that a fire at Yongbyon, North Korea's sole nuclear facility in the country's northwest, could lead to a disaster even larger than accident at the Ukrainian site, which is viewed as the worst of its kind in history.

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