Alexander Litvinenko

May 24 2002: ex-FSB spy Alexander Litvinenko Photograph: David Levene/freelance

November 20 2006: Litvinenko at University College Hospital in central London Photograph: Getty

November 24 2006: Police officers on duty outside University College Hospital in London, where Litvinenko died in an apparent poisoning Photograph: Martin Godwin/freelance

November 24 2006: Vladimir Putin answers journalist's question during a news conference in Helsinki. Putin condemned what he said was the use of the death of Litvinenko for political provocation Photograph: Denis Sinyakov/AFP

November 26 2007: Walter Litvinenko, father of Litvinenko, giving a statement outside the University College Hospital in London, hours after the death of his son Photograph: Odd Anderson/AFP

November 30 2006: Police activity outside Litvinenko's house in Muswell Hill, London Photograph: Martin Godwin/freelance

November 30 2006: Two police officers stand outside the boarded up Itsu restaurant Photograph: Scott Barbour/Getty

December 7 2006: The coffin of Litvinenko during his funeral at Highgate Cemetery in north London Photograph: Cathal McNaughton/PA

December 8 2006: Dmitry Kovtun, who met with Litvinenko in London Photograph: Alexander Zemlianichenko/AP

Italian academic Mario Scaramella is seen in this 2006 photo taken in Naples, southern Italy. Scaramella confirmed that he met with Litvinenko at a sushi bar in London on November 1 before the former agent was taken to an emergency room suffering from stomach pains and nausea Photograph: Salvatore Laporta/AP

December 11 2006: An officer of the Federal Criminal Police Office (BKA) examines a BMW car in Haselau, Germany. In focus is a mansion in the village of Haselau on the western outskirts of Hamburg where Kovtun's former mother-in-law lives. A witness told reporters a car was being 'practically dismantled' so that radiation counters could be held up to it Photograph: Sebastian Widmann/EPA

April 3 2007: Marina Litvinenko, widow of Alexander Litvinenko, at a press conference to launch the Litvinenko Justice Foundation in London Photograph: Martin Argles/Guardian

May 26 2007: Marina Litvinenko attends the 'Rebellion: The Litvinenko Case' photocall at the Palais des Festivals during the 60th International Cannes film festival Photograph: Peter Kramer/Getty

May 31 2007: Russian businessman Andrei Lugovoi takes part in a joint press conference with Dmitry Kovtun at the Interfax news agency. Andrei Lugovoi has claimed that British special services tried to recruit him to collect information compromising Russian President Vladimir Putin Photograph: Sergei Chirikov/EPA