Friends and family of poisoned former Russian spy Alexander Litvinenko on Thursday (December 7) paid their last respects at a ceremony at a Mosque in central London. Ahead of his burial, police stood guard at the entrance of the cemetry where a private ceremny was held. His funeral came as Russian prosecutors launched their own murder investigation into the death, in parallel to a British probe already under way. They also opened a criminal case into what they said was the attempted murder of Dmitry Kovtun, a Russian businessman who met Litvinenko at the time he fell ill. Kovtun has symptoms of radiation poisoning, prosecutors said. The moves came as British detectives pursued inquiries in Moscow into the politically charged case. On Wednesday (December 6), they and Russian investigators interviewed Kovtun who, along with fellow businessman and ex-KGB spy Andrei Lugovoy, met Litvinenko in a London hotel on November 1. Kovtun and Lugovoy are undergoing treatment in a Moscow hospital for radiation contamination. The British police had been hoping to interview Lugovoy on Thursday, but the meeting did not take place for "technical reasons" and would be held later, his lawyer, Andrei Romashov, told reporters. Litvinenko, a naturalised British citizen who was a sharp critic of the Kremlin, died in a London hospital on November 23 from poisoning with radioactive polonium 210. Litvinenko claimed on his death bed that Russian President Vladimir Putin had ordered his killing, an accusation that has strained relations between Moscow and London, spawned multiple conspiracy theories and revived memories of the Cold War. The Kremlin has denied any role in Litvinenko's death. Among the theories is that it could have been the work of rogue elements in Russia's intelligence services, working independently of the Kremlin. Russia's foreign minister said on Thursday political ties between Britain and Russia were not being affected by the investigation of the poisoning of the ex-KGB spy, Interfax news agency reported. "From our side the Scotland Yard investigation does not effect political relations (between Russia and Britain). I cannot judge how it looks from the British side. I have already said that an attempt to launch a campaign around this case, to make political sensation out of it has reached saturation point, including in the serious sections of the British media, which have been publicising their own views. From the very beginning, we have expressed our readiness to help the investigation, and we maintain this position. And when after two weeks, the British authorities asked for concrete steps by us to help their investigation, we immediately received British investigators who are currently working in Moscow," Sergei Lavrov said. On Monday (December 4) Lavrov expressed worries that ties could be damaged if insinuations of high-level Russian involvement continued. Meanwhile on Wednesday Italian Police seized the office in Naples of Mario Scaramella, an Italian contact of Litvinenko's. According to judicial sources, Scaramella has been placed under investigation on four counts: breaching secrecy rules in the Mitrokhin affair, involvement in a waste management scam in Naples, arms trafficking and possible involvement in suspected smuggling of uranium bars from Rimini to San Marino - an alleged incident he himself reported. Italian police raided the Naples offices of Scaramella's self-styled Environmental Crime Protection Program (ECCP) in what a magistrate called an "urgent action in connection with environmental crimes". Scaramella suggested the Naples police were "really looking" for Mitrokhin Commission documents, for which Sacramella worked until earlier this year. Set up by Silvio Berlusconi's former centre-right government, the Mitrokhin Commission trawled through the Italian part of a massive file of KGB contacts secretly compiled by Moscow archivist Vasily Mitrokhin. The Italian contact of Litvinenko describes himself as an academic but has no current institutional affiliations. He reportedly started out as an environmental consultant before becoming a security expert investigating former Soviet espionage and possible nuclear trafficking. Scaramella emerged as a central figure in the Litvinenko case because he met him in a London sushi bar on November 1, the day the Russian fell ill. Scaramella has been discharged from a London Hospital which had been monitoring him for radiation poisoning. He had been admitted to hospital last Friday (December 1) after polonium 210, the same poison that killed former Russian agent Litvinenko, was detected in his body. But doctors had said Scaramella had received a much lower dose than Litvinenko and was not showing any symptoms of radiation poisoning. ESPIONAGE