Alexander Litvinenko was a former officer of the Russian Federal Security Service (FSB) and KGB. After speaking critically about what he saw as corruption within the Russian government, he fled retribution to the UK, where he remained a vocal critic of the Russian state. Six years after fleeing, he was poisoned by two Russians in a suspected assassination.
On 1 November 2006, Litvinenko suddenly fell ill and was hospitalized. He died three weeks later, becoming the first confirmed victim of lethal polonium-210-induced acute radiation syndrome.