Transcript for US conducts military drills over Korean Peninsula

We'll move to escalating tension with North Korea. Military drills were conducted over the peninsula after questions swirl about them stealing sensitive war plans from South Korea. Martha Raddatz in Washington with the latest. Good morning, Martha. Reporter: Good morning, George. The tension between the U.S. And North Korea is relentless. Every day it seems more alarming news and this morning it's so disturbing. We know the U.S. And South Korea have updated war planning in the last few months doing lots of secret simulatings and exercises, but now reports that North Korea hacked into those classified plans through the south Korean military computer network. This according to a south Korean lawmaker who said those stolen plans include details about how Kim Jong-un would be removed from power, it's called the decapitation plan if war breaks out on the Korean peninsula, George. We're seeing bombing drills repetitively. A way to maintain the pressure and keep them contained. Reporter: You know, the secretaries of state and defense insist the U.S. Is on a diplomatic track, but I would call this coercive diplomacy because we've all heard fiery threats from the president and seen this repeated show of force which certainly does send a strong message. George. You got the president saying diplomacy cannot work here. Okay, Martha Raddatz, thanks very much.

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