Vladimir Putin critic Denis Voronenkov who fled Russia fearing for his life is shot dead by gunman in Ukrainian capital Kiev – as his distressed wife is pictured breaking down at the scene

A LEADING critic of Russian premier Vladimir Putin has been brutally gunned down in the Ukrainian capital Kiev.

Ex-Russian MP Denis Voronenkov, 45, was shot in the head in a daylight execution-style attack described by the Ukraine's president as "an act of state terrorism".

He had been a vocal critic of the Kremlin's actions in Crimea and eastern Ukraine, and had testified in a treason trial against ex-President Viktor Yanukovych —a firm Putin ally.

Dmitry Bilotserkovets, a Ukranian lawmaker, said Voronenkov was slaughtered just outside the Premier Palace hotel early on Thursday morning.

This was later confirmed by local police, with deputy chief Oleksandr Vakulenko suggesting the victim had "important information".

Voronenkov had been granted Ukrainian citizenship last year after losing an election and switching allegiance following the ousting of the country's pro-Russian leadership.

A former Communist Party member in the Russian Dumas parliament, he fled the country fearing for his safety after speaking out against Putin.

He left with his wife, the singer Maria Maksakova, who was also a politician. The couple have one infant son named Ivan.

She was pictured at the crime scene and fainted in shock. Some sources say she is pregnant.

Kiev Police Chief Andrei Krishchenko said the murder was likely a contract killing.

His attacker was injured by Voronenkov's bodyguard, who was himself also shot.

Both the attacker and the bodyguard are receiving treatment in a Kiev hospital.

Voronenkov had been due to meet another Putin critic and exiled Russian Ilya Ponomaryov.

Ponomaryov wrote that his friend was "an investigator who was deadly dangerous for Russian security agencies".

Russia launched a smear campaign against Voronenkov last year, laying on £4million fraud charges against him and his wife.

He told Ukrainian media that Russia was going through a "pseudo-patriotic frenzy" similar to Nazi Germany.

Petro Poroshenko, Ukraine’s president, was briefed on the killing by his head of security before blasting the "cunning murder".

He said the killing was "act of terrorism on the part of Russia, which he was forced to leave for political reasons", a presidential spokesperson wrote.

Ukraine’s prosecutor general, Yuri Lutsenko, described the "cynical" attack as “the usual kind of Kremlin retribution”.

And Anton Herashchenko, an adviser to the Ukrainian Interior Ministry, said: "It is an ordered political murder, made for the purpose of intimidating all those Russian deputies and officials who try to escape from Russia to the West or to Ukraine."

The aim was to gag those like Voronenkov who seek to "tell the truth about how the punitive Russian apparatus works".

He claimed: "He was killed in retaliation for the fact that he and his wife gave truthful testimony about how the annexation of the Crimea and the attack on the Donbass was prepared."

The Kremlin denied any involvement in the murder, saying the accusations are "absurd".

Putin's spokesman said the Russian president had been informed of the shooting, and angrily denied Russian links to his shooting.

"We think that any insinuations that are already being voiced about the same old Russian trace are absurd," he said.

He declined to say more. "It is not our theme," he said.

There were critical voices about Voronenkov from his former colleagues.

His mother in law Lyudmila Maksakova was quoted as saying: "Well, thank God, what else is there to do with him?

"Thank God that in the end... a man who was so mean, he is a military man, he would have been shot for treason long ago."

Leading Communist Sergey Obukhov claimed Voronenkov himself was to blame for his death by giving himself up to foreign special services, having left Russia and having accepted the citizenship of Ukraine.

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