A public inquiry into the killing of former Russian spy Alexander Litvinenko has concluded that President Vladimir Putin probably approved his assassination. But who was he and why did his death cause such controversy?
23 Nov 2006 - Litvinenko dies three weeks after having tea with former agents Andrei Lugovoi and Dmitri Kovtun in London
24 Nov 2006 - His death is attributed to polonium-210
U.K.Home Office forensic pathologist Dr Nathaniel Cary said the post-mortem examination carried out on Mr Litvinenko's body had been correctly described as the "most dangerous... ever undertaken in the Western world". He and his colleagues had to wear white suits, protective gloves and specialised hoods with air pumped into them through a filter during the process.
Results of that examination suggested Mr Litvinenko had died after being poisoned with the radioactive substance polonium-210.