A pro-Russian militiaman guards a barricade in front of the flag of so called Donetsk Republic outside a regional police building in eastern Ukrainian city of Slavyansk on April 14, 2014. Ukraine’s latest ultimatum to pro-Kremlin militias who have seized buildings across a swath of the separatist east expired on Monday without any sign of the gunmen ready to give in. AFP PHOTO / ANATOLIY STEPANOVANATOLIY STEPANOV/AFP/Getty Images