TEXT: Opposition leader Boris Nemtsov speaks to the media during a gathering of opposition supporters in central Moscow March 17, 2012. The Russian opposition politician and former deputy prime minister Boris Nemtsov has been shot and killed by four shots in central Moscow, the Russian government said in a statement, according to the Interfax news agency. Picture taken March 17, 2012. REUTERS/Mikhail Voskresensky/Files (RUSSIA - Tags: POLITICS CIVIL UNREST)