Russia's president said Nemtsov's death was a shameful tragedy. Nemtsov was gunned down near the Kremlin on Friday. His supporters blame Russian authorities.
Russian President Vladimir Putin is in Cairo for talks with Egyptian President Abdel-Fattah el-Sisi, one day before a critical meeting in Minsk over the future of Ukraine.
A series of military confrontations and growing tensions between Western Europe and Russia show how ill-prepared European countries are after years of cutbacks.
Russian author Mikhail Bulgakov's classic, The Master and Margarita, ridiculed Soviet leaders and bureaucracy. It wasn't published until 27 years after his death, but it still resonates with Russians.
