Overnight shelling in the eastern Ukrainian city of Donetsk killed three people and wounded five as government forces tighten their grip on the pro-Russian rebel stronghold, the city council said Thursday, according to AP. In a statement on its website, the council said several residential buildings have been damaged by shelling in a neighborhood about 7 kilometers (4 miles) from the city's central square. There was no mention of further aerial attacks, which were reported in the city on Wednesday. As the rebels struggle to push back Kiev's forces, fears of Russian intervention have grown. Western leaders have accused Russia of massing troops on the border with Ukraine, although Russia has denied claims about a military buildup. In Kiev, meanwhile, demonstrators confronted city workers who were attempting to clear a central square Thursday, lighting tires on fire in protest against the city government's move. Dark plumes of acrid smoke from burning rubber rose above Independence Square as workers guarded by armed men in camouflage dismantled some of the barricades surrounding the area.