A Ukrainian soldier inspects a trailer at a checkpoint outside the city of Slaviansk
A Ukrainian soldier inspects a trailer at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: POLITICS CIVIL UNREST)
A Ukrainian policeman walks past pro-Russian activists blocking the entrance to a television station in Donetsk
A Ukrainian policeman walks past pro-Russian activists blocking the entrance to a television station in Donetsk, eastern Ukraine April 27, 2014. Pro-Russian separatists on Sunday seized control of the offices of regional state television in the eastern Ukrainian city of Donetsk, a Reuters reporter outside the building said. The reporter said four separatists in masks, with truncheons and shields, were standing at the entrance to the building controlling access, while more separatists in camouflage fatigues could be seen inside. REUTERS/Baz Ratner (UKRAINE - Tags: MEDIA CIVIL UNREST POLITICS)
A Ukrainian soldier stands guard at a checkpoint outside the city of Slaviansk
A Ukrainian soldier stands guard at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: MILITARY POLITICS CIVIL UNREST)
Ukrainian soldiers sit on top of an armoured personnel carrier at a checkpoint outside the city of Slaviansk
Ukrainian soldiers sit on top of an armoured personnel carrier at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: POLITICS CIVIL UNREST)
Ukrainian soldiers sit on top of an APC at a checkpoint outside the city of Slaviansk
Ukrainian soldiers sit on top of an armoured personnel carrier (APC) at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: MILITARY POLITICS CIVIL UNREST)
Ukrainian soldiers sit on top of an armoured personnel carrier at a checkpoint outside the city of Slaviansk
Ukrainian soldiers sit on top of an armoured personnel carrier at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: POLITICS CIVIL UNREST)
A Ukrainian soldier stands guard near an APC at a checkpoint outside the city of Slaviansk
A Ukrainian soldier stands guard near an armored personnel carrier (APC) at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: MILITARY POLITICS CIVIL UNREST)
Ukrainian soldiers stand guard at a checkpoint outside the city of Slaviansk
Ukrainian soldiers stand guard at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: POLITICS CIVIL UNREST)
A Ukrainian soldier stands guard at a checkpoint outside the city of Slaviansk
A Ukrainian soldier stands guard at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: POLITICS CIVIL UNREST)
A Ukrainian soldier stands guard near an APC at a checkpoint outside the city of Slaviansk
A Ukrainian soldier stands guard near an armored personnel carrier (APC) at a checkpoint outside the city of Slaviansk April 27, 2014. The leader of separatist rebels holding a group of international observers in the Ukrainian city of Slaviansk said he was scheduled on Sunday to meet a delegation of mediators who were on their way to negotiate the observers' release. REUTERS/Gleb Garanich (UKRAINE - Tags: MILITARY POLITICS CIVIL UNREST)