The U.S. is testing procedures for the emergency evacuation of its citizens from South Korea in an unusual military exercise in which a small group of Americans will be flown to Dallas in conditions meant to simulate preparation for conflict.

With a possible summit meeting between President Donald Trump and North Korean leader Kim Jong Un approaching and inter-Korean talks nine days away, U.S. officials have sought to play down the exercise. Dubbed “Focused Passage,” the exercise began without fanfare earlier this week.

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