KYIV, Ukraine (AP) — Pro-Kremlin officials have blamed Ukraine for a rocket attack that struck the mayor’s office in a key Ukrainian city controlled by the separatists. The municipal building in Donetsk was seriously damaged by the rocket attack. Separately, Ukrainian officials said Russian rockets struck a city across from the Zaporizhzhia nuclear power plant, injuring six people. Late Saturday, a Washington-based think tank late accused Moscow of conducting “massive, forced deportations of Ukrainians” which it said likely amount to ethnic cleansing. The attacks on both sides came as Russia has lost ground in the nearly seven weeks since Ukraine’s armed forces opened their southern counteroffensive.