Transcript for UN to hold emergency meeting on Ukraine, Russia

We'll move overseas now to a dangerous confrontation between Russia and Ukraine. Three ships near the black sea, and they scheduled an emergency council meeting for the standoff, and Martha Raddatz is tracking the latest from Washington. Reporter: A critical U.S. Strategic partner, already simmering, but this could bring things to a boil. The Ukrainians say Russia prevented its ships from transitting a key waterway. In a video released this morning, it shows a Russian vessel ramming a Ukrainian tugboat, and they say they then opened fire injuring several sailors and seizing several of its vessels. Russia says it had warned the ships to stop. Russia scrambled military planes and Ukraine's president is asking that martial law be imposed. Nato was calling for restraint on both sides as the U.N. Security council prepares to meet just hours fro George. And elections as well. Thanks very much.

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