Transcript for Newly released video appears to show assassination of Putin critic

Now we're going to head overseas to the disturbing images emerging from Ukraine. The undercover video showing the assassination of a vocal critic of Russian president Vladimir Putin. It's the latest of a series of deadly incidents raising new questions tonight. ABC's Ron Claiborne tracking this. Reporter: In this newly released chilling video, the Russian defector can be seen. That's Denis voronenkov. His bodyguard on his left. Watch as a man approaches from behind. Steps up to voronenkov, and shoots him. The bodyguard charges the attacker. As the victim lay on the ground, his body can be seen firing at the fleeing assailant, fatally wounding him. But voronenkov was dead on the street in the Ukrainian capitol, and officials there immediately blamed Russia calling the murder an act of state terrorism. Voronenkov, a member of the Russian parliament, fled to Ukraine while under investigation for corruption. He spoke out against Putin. Over the years, a number of Putin critics have been murdered. He had given several interviews saying his life was in danger. Two years ago, Boris Nemtsov, a prominent politician, gunned down near the Kremlin. And in 2006, Alexander L lit V litvinenko was poisoned. His murderer was carrying a passport, but people say Russia ordered the hit to silence him. A spokesman for Putin says he hopes that an Ukrainian investigator is able to solve the murder, and Mr. Putin invited the victim's widow to return to Russia. We'll see if they accepts that invitation. Thanks so much. Now to the U.S. Military

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