BOLINGBROOK, Illinois (CNN) -- The family of a missing Illinois woman has an "eerie feeling of dread" after a ruling that her husband's previous wife was a victim of homicide, a spokeswoman said.
Investigators have said Drew Peterson is a suspect in the disappearance of his fourth wife, Stacy Peterson.
The October disappearance of Stacy Peterson, the fourth wife of former Bolingbrook police Sgt. Drew Peterson, prompted questions about Kathleen Savio, his third wife.
Savio was found drowned in a bathtub in 2004, with a gash on her head and blood in her hair. Her death was ruled accidental by a coroner's jury.
Savio's body was exhumed in November, and a second autopsy was performed by certified forensic pathologist Larry Blum.
"We have been investigating this as a murder since reopening the case in November of last year," James Glasgow, the state's attorney in Will County, said in a written statement Thursday. "We now have a scientific basis to formally and publicly classify it as such."
Drew Peterson, 53, has not been named a suspect in Savio's death. But authorities have said that he is considered a suspect in Stacy Peterson's disappearance.
Drew Peterson said that he last spoke to Stacy Peterson on the night of October 28 and that he believes she ran off with another man. She has not been seen since. See a timeline of the Peterson case »
The couple had been married four years and had two children. Drew Peterson also has children from a previous marriage.
State police and grand jury investigations continue into Stacy Peterson's disappearance. Prosecutors have said that both entities are also investigating Savio's death, so if any criminal charges are warranted, they would probably not be filed until the grand jury completes its investigation and hands up an indictment.
But "it leaves one an eerie feeling of dread," said Pam Bosco, a spokeswoman for Stacy Peterson's family, on Thursday night.
"We realize that Kathleen and Stacy had one common denominator, and that was Drew Peterson, so we look forward to this investigation that's ongoing right now with Kathleen's death and Stacy's disappearance."
Drew Peterson answered his door Friday and told CNN's Susan Roesgen, "We are not talking to anybody. You can call my lawyer, Joel Brodsky, in the next couple of days."
Brodsky appeared Thursday night on CNN Headline News' "Nancy Grace" and noted that Savio's autopsy showed a mild thickening of her heart's mitral valve. He theorized that "from her mitral valve thickening, she has a mild heart infarction [heart attack]. She becomes unconscious, hits her head and drowns in the water." Watch Nancy Grace discuss Kathleen Savio's death »
On Friday, Brodsky told CNN affiliate CLTV, "We have a guy who has one wife die of an accident and another one who ran off, which may make him unlucky, but nothing mischievous about either of those two things."
Drew Peterson and Savio divorced before he married Stacy Peterson. Bosco said family members asked Stacy Peterson whether she believed that Savio drowned accidentally but said the woman defended her husband, saying Savio hit her head and drowned. Bosco said family members liked Drew Peterson and tried to put their suspicions aside.
Savio's family, however, has said they always believed that her death was not an accident. Melissa Doman, Savio's niece, said relatives think Drew Peterson stood to gain about $3 million from Savio's death, based on the couple's shared business interests in a bar and a printing company, their home and payments from five life insurance policies Savio had on herself.
The new autopsy report has not been released because of the ongoing investigation, and prosecutors won't say what led Blum to come to the conclusion that Savio's death was a homicide rather than an accidental drowning.
Blum performed the second autopsy November 13. A third autopsy was performed November 16 by noted pathologist Michael Baden, at the request of Savio's family, authorities said. The results of the third autopsy were not disclosed because of the ongoing investigation. E-mail to a friend
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