A man who says he found the body of a former police officer's third wife in a bathtub said he was summoned by a grand jury convened to review her death.

Steve Carcerano, a friend of Kathleen Savio's ex-husband Drew Peterson, said he was called by the grand jury, but did not get to testify Wednesday and was told to return at a later date. Illinois State Police have said Peterson's brother, Paul, also was subpoenaed by a grand jury.

Investigators initially said Savio's death was an accidental drowning when she was found in the bathtub three years ago. But now, with Peterson's fourth wife missing for more than two weeks, authorities are re-examining the circumstances of her death.

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Savio's body was exhumed this week at the request by state's attorney James Glasgow, who has said after examining evidence he believes her death was a homicide staged to look like an accident.

Peterson, 53, who resigned this week as a Bolingbrook police sergeant, has not been named a suspect in Savio's death. But he is a suspect in the disappearance of his fourth and current wife, Stacy, who was last seen Oct. 28 and whose case authorities have called a possible homicide investigation.

Click here to read Jamie Colby's blog: "Inside Drew Peterson's House."

Drew Peterson has denied any involvement in either case and said he believes his 23-year-old wife left him for another man and is alive.

He told America's Most Wanted he hopes she, "exposes herself to be alive and well."

Click here to read the report from America's Most Wanted.

Vicki Connolly, Peterson's second wife, told the Chicago Tribune that during their marriage an increasingly controlling Peterson hit her and told her he could kill her and make it look like an accident.

Connolly told the Tribune she did not believe Peterson would ever kill her, but confided in Bolingbrook police officers who she considered friends.

"So they would know he said these things to me," Connolly told the Tribune.

The husband of Peterson's first wife told WGN-TV on Wednesday his wife hasn't talked to Peterson in more than ten years. But he said his wife never has mentioned Peterson being violent or threatening.

"She didn't have any of that kind of problem with him that long ago," said Dave Brown.

Documents released by Savio's family show she had accused Peterson of once stealing her car while she was in church with one of her children. She also, according to one letter the family said was sent to the Will County State's Attorney's office in November 2002, accused Peterson of beating her a number of times so severely she "ended up in the emergency room."

She also described in the letter an incident in which she believed he would kill her: "He pulled out his knife that he kept around his leg and brought it to my neck."

Charles Pelkie, a spokesman for the Will County State's Attorney's Office, said it remains unclear if that letter ever came to the office. He said it was not in the files Glasgow read when he began reinvestigating Savio's drowning.

But many allegations in the letter are consistent with those Savio made in an order of protection filed against Drew Peterson in 2002, as well as accounts given by her family members.

Attorney Fred Morelli, who once represented Peterson, said he never heard the knife claims about his former client.

"That's the first I've heard of that," Morelli said. "That's crazy. ... (Peterson) was a very pleasant, personable fellow. Other than that, I don't know."