Associated Press: Drew Peterson, the former police sergeant who went on a high-profile media blitz after his fourth wife's disappearance, is due to make his first court appearance Friday in the drowning death of an ex-wife found dead in an empty bathtub in 2004.

Peterson, 55, was scheduled to be arraigned on charges of first-degree murder in the death of his third wife, Kathleen Savio.

He was arrested during an evening traffic stop Thursday near his Bolingbrook home and was held on $20 million bond, Illinois State Police Capt. Carl Dobrich said.

"We are very confident in our case," Will County State's Attorney James Glasgow said.

Savio's body was found in a dry bathtub, hair soaked in blood from a head wound, just before the couple's divorce settlement was finalized. Her death originally was ruled an accidental drowning but authorities later said it was a homicide staged to look like an accident.

The indictment alleges that "Peterson on or about Feb. 29, 2004 ... caused Kathleen Savio to inhale fluid," causing her death.

Savio's family has long voiced suspicions, saying she feared Peterson and told relatives if she died it would not be an accident. Their fears resurfaced after the October 2007 disappearance of Stacy Peterson, then 23.

Drew Peterson is a suspect in the disappearance, which police have called a possible homicide. But he has not been charged and has repeatedly said he thinks Stacy Peterson ran off with another man.

"I guess I should have returned those library books," a handcuffed Peterson said as state police led him into headquarters following his arrest, according to The (Joliet) Herald-News.

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