TOPSHOTS Pro-Russia protesters throw stones as they storm a regional police building in the eastern Ukrainian city of Horlivka (Gorlovka), near Donetsk, on April 14, 2014. A few hundred pro-Russia activists seized the building after an hour-long storming. Ukraine's interim president on April 14 made a dramatic about-face aimed at defusing tensions in the separatist east by backing a national referendum on turning the ex-Soviet republic into a federation with broader regional rights. AFP PHOTO/ ALEXEY KRAVTSOV