RALEIGH, N.C. — A man suspected of decapitating his 4-year-old daughter and leaving the body for her mother to find in their suburban home was arrested in Washington, D.C., early Saturday, authorities said. Investigators have not found any history of domestic or mental health problems at the home, and still have no leads as to a possible motive in the killing, said Clayton police Lt. Jon Gerrell. Amber Violette told police Friday evening she had found her daughter, Katlin, with her head severed from her body, police said. An "edged weapon" believe to have been used in the killing was...