Description:Amateur video out of Syria shows empty streets in the rebellious city Homs. The video, which could not be independently verified by Reuters shows smoke rising from buildings amid the sound of relentless fire. Activists and residents say hundreds of people have been killed over the past week as government forces try stamp out opposition in Homs. As dawn broke Thursday, rocket and mortar fire rained down again on Homs. The United Nations chief has condemned the ferocity of the government assault.(1:47)