Masked pro-Russian protesters stand guard outside a regional government building in Donetsk, eastern Ukraine April 19, 2014. A day after an international deal in Geneva to defuse the East-West crisis in Ukraine, pro-Russian separatists vowed not to end their occupation of public buildings and Washington threatened further sanctions on Moscow if the stalemate continued. REUTERS/Marko Djurica (UKRAINE - Tags: POLITICS CIVIL UNREST)