Transcript for Thousands march in anti-corruption protests across Russia

Who would turn overseas tonight to a massive day of protests in Russia. A wave of anti corruption rallies across the country the largest in years demonstrators clashing with police in Moscow hundreds arrested. A vocal opponent of Russian president Vladimir Putin did taint. And new questions being raised after surveillance video appears to show the assassination. Of another Putin critic here's ABC's Gina practiced. Tonight we're shaking turmoil. A stunning and rare display and thousands erupting in protest. Russian police in riot here cracking down. Ripping apart crowds with night sticks smacking protesters in the heart of Moscow. The government calling the rally illegal at least 500 arrested many horse and the police vans this man plunged as he's led away. The demonstrations all across Russia accusing president Vladimir Putin's government on widespread corruption. The organizers of anti protest highs profiled. Kremlin critic Alexi know Vallone also hold into custody supporters trying to block police says they take him to jail. I'm not behind bars. But challenging authority in Russia is risky. On Thursday this surveillance video capturing the execution style killing of prudent folk. Dennis run a cough in Ukraine Kiev calling it a Kremlin hit Moscow calling back absurd. Another proven critic a Russian lawyer critically injured in a suspicious plunge from his Moscow apartments. Russia hasn't seen protests like today's teen hears the police response swift and heavy handed. The Kremlin is sure to find such public anger unsettling. And not easy to ignore.

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