CNN  — 

Russia was responsible for killing Alexander Litvinenko, a former Russian agent turned Kremlin critic who died in London by polonium poisoning in 2006, the European Court of Human Rights (ECHR) said Tuesday.

The ruling found that “Russia was responsible for assassination of Aleksandr Litvinenko in the UK.”

“The Court found in particular that there was a strong prima facie case that, in poisoning Mr Litvinenko, Mr Lugovoi and Mr Kovtun had been acting as agents of the Russian State,” it said, referring to the names of two Russian agents accused of killing Litvinenko.

The court also ruled that Russian authorities “had not carried out an effective domestic investigation capable of leading to the establishment of the facts and, where appropriate, the identification and punishment of those responsible for the murder.”

The ECHR verdict supports the findings of a 2016 British inquiry that found that the two Russian agents poisoned Litvinenko at a London hotel bar in 2006 by spiking his green tea with the highly radioactive polonium-210.

In a statement from his deathbed in London in November 2006, Litvinenko said he had no doubt about who was to blame for his imminent death.

“You may succeed in silencing one man, but the howl of protest from around the world will reverberate, Mr. Putin, in your ears for the rest of your life,” he said.

The British inquiry said that Putin “probably approved” the ex-spy’s killing.

The Kremlin has always denied the accusation, as did the two agents accused of the poisoning, whom the Russian government has refused to extradite to the UK.

On Tuesday, the ECHR said that “the court found it established, beyond reasonable doubt, that the assassination had been carried out by Mr Lugovoi and Mr Kovtun.”

“The planned and complex operation involving the procurement of a rare deadly poison, the travel arrangements for the pair, and repeated and sustained attempts to administer the poison indicated that Mr Litvinenko had been the target of the operation,” it said.

The ECHR ruling concluded that if the men been carrying out a “rogue operation,” it would be up to Russian authorities to prove that theory.

“However, the government had made no serious attempt to provide such information or to counter the findings of the UK authorities,” it said.

Kremlin spokesman Dmitry Peskov pushed back on the ruling Tuesday, saying that Moscow was “not ready to take cue from such conclusions,” and that “it is unlikely that the ECHR has the authority or the technological capabilities to have information on this matter.”

“As you know, there are still no results of this investigation, so making such statements is at least unfounded,” Peskov said, referring to a domestic criminal investigation launched in December 2006 that the ECHR said they have few details about.

Spy-turned-whistleblower

Litvinenko had worked for the FSB, Russia’s successor agency to the KGB, the former Soviet secret police and intelligence agency. While his specialty was in tackling organized crime, his last job at the agency, after the collapse of the Soviet Union, was heading up its anti-corruption department. From that position, he made many enemies.

In 1998, he went public with allegations that he had been asked to examine the possibility of assassinating a wealthy businessman. He was subsequently fired from the agency, and fled Russia, according to the ECHR.

He also blamed the agency for orchestrating a series of apartment bombings in Russia in 1999 that left hundreds dead and led to Russia’s invasion of Chechnya later that year.

In 2001 Litvinenko and his family were granted asylum in the UK, acquiring British citizenship in 2006. His widow, Marina, who now is known as Maria Anna Carter and still lives in London, brought the case to the ECHR in 2007.

Litvinenko is not the first Putin critic to be allegedly poisoned.

In 2018, the former Russian agent Sergei Skripal and his daughter Yulia were sickened by Novichok, a military-grade nerve agent, In Salisbury, England. British prosecutors charged two Russian nationals, – who have now been officially identified as officers of the Russian military intelligence service, Anatoliy Chepiga and Alexander Mishkin – over the poisonings that year. London Metropolitan police authorized charges against a third Russian intelligence agent, identified as Denis Sergeev, aka “Sergey Fedotov,” on Tuesday.

And in August 2020, prominent opposition leader Alexey Navalny was poisoned with the same lethal nerve agent.

CNN’s Anna Chernova, Seb Shukla and Lindsay Isaac contributed to this report.