Pro-Russian separatists guard a checkpoint near the town of Slaviansk

Pro-Russian separatists guard a checkpoint near the town of Slaviansk in eastern Ukraine May 2, 2014. Ukraine launched a “large-scale operation” to retake the eastern town of Slaviansk, pro-Russian separatists there said on Friday, in an escalation of violence in what has become the worst confrontation between Russia and the West since the Cold War. REUTERS/Baz Ratner (UKRAINE – Tags: POLITICS CIVIL UNREST)