SLOV'YANS'K, UKRAINE - APRIL 21:  A pro-Russian militant stands guard in front of the occupied Ukraine Security Service building on April 21, 2014 in Slovyansk, Ukraine. Pro-Russian militants have taken over the building and other government buildings in the city and are demanding independence from Ukraine. Other pro-Russian activists have been occupying government buildings in other eastern Ukraine cities in recent weeks making similar demands.  (Photo by Scott Olson/Getty Images)