PRAGUE, December 5, 2006 (RFE/RL) -- A team of British investigators has begun work in Moscow on the case of poisoned former Russian security officer Aleksandr Litvinenko. The investigators are in Moscow to question several Russians who met with Litvinenko in London, where he died after being poisoned with a radioactive isotope, polonium-210. It remains unclear if Litvinenko was intentionally poisoned. Scotland Yard, the headquarters of the London metropolitan police service, is not expected to comment while the investigation is under way. Religious Conversion Litvinenko's father, Valter, told RFE/RL's Russian Service his son converted to Islam shortly before his death...