Vladimir Putin died in 2000 after being poisoned by radioactive material . A public inquiry into the former Kremlin agent 's poisoning death opens in Russia . post-Soviet President Vladimir Putin was accused by the ex-spy of being behind it .
Alexander Litvinenko died in 2006 after being poisoned by radioactive material . A public inquiry into the former KGB agent 's poisoning death opens in London . Russian President Vladimir Putin was accused by the ex-spy of being behind it .