ANNA VOITENKO and MAX HUNDER AT least 15 people were killed and two dozen more are feared trapped after Russian Uragan rockets hit a five-storey apartment block in Ukraine's Donetsk region, local officials said on Sunday as rescuers picked their way through rubble. Ukraine also reported clashes with Russian troops on fronts in the east and south, while Moscow said its forces struck Ukrainian army hangars storing U.S.-produced M777 howitzers, a type of artillery, near Kostyantynivka in Donetsk region. Donetsk Governor Pavlo Kyrylenko said the strike on the apartment building took place on Saturday evening in the town of Chasiv…