Alexander Litvinenko

Alexander Litvinenko was a Russian-British former Federal Security Service officer who died in London in 2006 after being poisoned with polonium-210.

Litvinenko inquiry: A British public inquiry into Litvinenko’s death, published in 2016. It concluded that Andrey Lugovoy and Dmitry Kovtun carried out the poisoning and that senior Russian officials likely approved it.
Polonium-210: A radioactive isotope of polonium that emits alpha particles and has a half-life of about 138 days. It was the radioactive poison used to kill Litvinenko.
Federal Security Service: Russia’s principal domestic security and counterintelligence agency, commonly abbreviated FSB. Litvinenko served in the agency before leaving Russia and becoming a critic of its leadership.
United Kingdom–Russia relations: The political, diplomatic, and economic relationship between the United Kingdom and Russia. Litvinenko’s killing triggered diplomatic expulsions and deepened distrust between the two governments.
Russian criminal investigation into Litvinenko’s death: A Russian investigation into Litvinenko’s death that did not result in the suspects’ prosecution in Britain. Its course and conclusions differed from the British investigation, which attributed the killing to named Russian suspects.
Andrey Lugovoy: A Russian politician and former security officer identified by the British inquiry as a principal in Litvinenko’s poisoning. The inquiry found that he administered the fatal polonium dose with Dmitry Kovtun.
Alpha particle: A particle consisting of two protons and two neutrons, emitted during some radioactive decays. Polonium-210 emits alpha particles, which are highly damaging when radioactive material enters the body.
Boris Berezovsky: A Russian businessman and political figure who lived in exile in the United Kingdom. Litvinenko worked for Berezovsky after leaving Russia and became part of his circle in Britain.
State-sponsored assassination: The deliberate killing of a person authorized or carried out by a state or its agents. British findings framed Litvinenko’s death as an operation likely approved at the highest levels of Russia’s government.
Murder trial in absentia: A criminal trial conducted while the accused person is absent from court. Lugovoy was not tried in Britain because Russia refused extradition, leaving no British criminal verdict against him.

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