Expert: The radioactive material used to kill one of Putin's most prominent critics came from a single plant in Russia

Alexander Litvinenko spyvia The TelegraphAlexander Litvinenko.

The radioactive material used to poison one of Putin’s most prominent critics in 2006 likely came from a highly secure facility in Russia, the Financial Times reports citing an ongoing British public inquiry into the murder, which took place in London.

British physicist Norman Dombey told the inquiry into the 2006 poisoning of Russian intelligence operative Alexander Litvinenko that the polonium-210 used in his murder could only have come from a single heavily guarded Russian plant.

“The [polonium-210] used to poison Mr Litvinenko was prepared at the Avangard facility in Sarov, Russia,” Dombey told the inquiry in written evidence. “In my opinion, the Russian state or its agents was responsible for the poisoning.”

According to Dombey, Avangard was the only commercial producer of polonium-210 in the world at the time of the murder. Although the US, UK, Canada, and China all produced polonium from the 1950s to 1970s, production for commercial use had ceased — except at Avangard.

Dombey believes the Russian government is to blame for Litvinenko’s death. In his view, the polonium’s transport “from Avangard to whatever Russian institution was able to convert it to a soluble form” necessitated the involvement of the Kremlin.

The conversion of polonium-210 into a soluble form was essential for poisoning Litvinenko. According to the US Nuclear Regulatory Commission (NRC), polonium-210 emits alpha radiation which cannot penetrate paper or skin rendering the substance fairly innocuous outside the body.

But if polonium-210 is ingested or inhaled, the material can be fatal in even small amounts. The NRC cautions that ingested polonium can quickly “destroy major organs, DNA, and the immune system.”

These properties make polonium-210 a reliably deadly poison. The material would pose little harm to the handlers of the material, but would prove fatal to whoever ingested it.

The UK believes that Litvinenko, a defector from Russia’s FSB intelligence agency, was poisoned by two Russian agents in a London hotel.

Andrei LugovoiREUTERS/Maxim ShemetovOne of the prime suspects in the murder of Litvenenko, Andrei Lugovoi.

After Litvinenko’s defection from the FSB, he moved London where he became an outspoken critic of Putin and his regime. One of the two prime suspects in the murder is Andrei Lugovoi, a member of Russia’s lower house of parliament.

The Kremlin bestowed upon Lugovoi a medal of honour earlier in the month for “his great contribution to the development of the Russian parliamentary system and his active role in lawmaking.”

British intelligence believes that Lugovoi personally slipped the polonium into Litvinenko’s tea during a meeting at the Millennium hotel in London in November 2006. Twenty-three days later, Litvinenko died in a London hospital.

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