Transcript for Successful North Korean rocket engine ground test reported

Lama, thank you. And to North Korea, and the ground test of its new rocket engine. This, as secretary of state Rex tillerson was just wrapping up his first trip to Asia. Here's Bob woodruff with more. Reporter: North Korea's increasingly dangerous leader Kim Jong-un smiled as he watched the firing of the rocket engine himself, calling it a new birth a revolutionary breakthrough for the nation's rocket industry. Late today, president trump called out North Korea. I had meetings on north Korea. He's acting very, very badly. I'll tell you, he's acting very badly. Reporter: The test coming just as secretary of state tillerson wrapped up his three-country trip to Asia, during which he said the U.S. Will change its strategy dealing with North Korea. Let me be very clear. The policy of strategic patience has ended. Reporter: Suggesting that preemptive strikes by the U.S. Are on the table. Tensions on the peninsula are quite high right now. Things have reached a rather dangerous level. Reporter: Was the test coincidental or on purpose to coincide with secretary tillerson's meeting today with Chinese president XI jinpin? Kim Jong-un has done that before, including when he launched a ballistic missile last month while Japan's president Abe was meeting president trump at his golf club in Florida. As for the new type of engine, if it is what Kim Jong-un says that it is, it could send his rockets further into space for science, or to launch missiles closer to his possible targets like the United States. Tom? Bob, thank you. Back here at home, we're also following another security

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