(CNN) -- Drew Peterson, the former police sergeant who authorities call the prime suspect in the disappearance of his fourth wife, Stacy Peterson, has been indicted on murder charges related to his third wife, Kathleen Savio, the Illinois state attorney's office said. Drew Peterson was arrested Thursday on murder charges relating to his third wife, Kathleen Savio. Illinois State Police said Peterson was taken into custody about 5:30 p.m. Thursday after a traffic stop near his home. Police had staked out his home all day, said police Capt. Carl Dobrich, but waited for Peterson to leave to arrest him out of concern for his three children, who were inside the house.
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Dad of girlfriend: I'm glad justice finally came -- before he hurt my daughter"
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Drew Peterson arrested in the slaying of his third wife, Kathleen Savio
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Renewed interest in Savio's death came after Peterson's fourth wife disappeared
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Peterson, through his attorney, denies any wrongdoing in either case
Pelkie said the grand jury continues to meet and is studying the possibility of charges in @placeholder's disappearance.