Renewed fighting between Somalia's radical Shebab militia and African Union-backed government forces has killed at least 15 civilians in the capital, officials and medical sources said Thursday. More than 50 civilians were also wounded in the late Wednesday firefight sparked by an insurgent attack on AU peacekeepers and government forces in southern Mogadishu. "At least 15 civilians died and many others were injured in the shelling," police officer Dahir Mohamed said. Witnesses said mortars hit their homes as they were preparing to go to bed.