A former Russian lawmaker who once compared Russian President Vladimir Putin to Adolf Hitler was shot and killed in Kiev, Ukraine, on Thursday morning.
Denis Voronenkov was killed near a hotel in the center of the Ukrainian capital, Bloomberg reports. His bodyguard was also injured in the shooting. He returned fire and wounded the attacker.
Voronenkov, a former opera singer and member of Putin's ruling party, fled Russia for Ukraine last year, becoming a citizen in February.
Voronenkov was testifying in a treason case against former Ukrainian President Viktor Yanukovych, who was ousted in deadly protests three years ago and now lives in Russia.
Voronenkov described the situation in Russia as similar to "Hitler's Nazi Germany."
The Kremlin dismissed accusations of Russian involvement as "absurd."
Elsewhere in Ukraine, a massive fire at a military arsenal prompted 20,000 evacuations Thursday. Defense Minister Stepan Poltorak said the fire had likely been started by Russian or pro-Russian separatist saboteurs.