Chicago ? The death of a former suburban Chicago police officer’s third wife has been ruled a homicide after a second autopsy showed she drowned, a prosecutor said Thursday.

The death of Kathleen Savio four years ago was initially ruled an accident. She was found dead in her bathtub shortly before her divorce with Drew Peterson was finalized.

Savio’s body was exhumed late last year after Peterson was named a person of interest in the disappearance of his fourth wife, Stacy. He has said Stacy Peterson ran off with another man, but her relatives deny any affair and say she would not have willingly left her two young children.

Peterson, 54, has denied any involvement in either case, and he has not been charged with wrongdoing.