Updated 10/13/11 – 4:48 p.m.

CHICAGO (CBS) — In the first 24 hours of the latest attempt to identify the eight unidentified victims of serial killer John Wayne Gacy, Cook County Sheriff Tom Dart says authorities have received a flood of calls.

As CBS 2’s Derrick Blakley reports, calls to Dart’s office since Wednesday have produced what the sheriff calls 25 “legitimate hits” – information about young males who fit the profile of Gacy’s targets and who disappeared during the time of Gacy’s terror.

“It’s very heartening within just the first 24 hours, the amount of response that we’re getting,” Dart said Thursday.

The eight unidentified victims of the notorious serial killer, who was arrested in December 1978 and executed 16 years later, have been exhumed so that lab experts could take DNA samples and compare them against the DNA of possible parents, siblings or children.

Dart hoped that relatives of young men who vanished during the time of Gacy’s killing spree would find the courage to come forward and, so far, he hasn’t been disappointed.

“They’re giving us the age of their loved one. It was right in the target zone. The time of missing was the same target zone,” Dart said of the legitimate leads that have come in. “And even throwing in some additional factors where they’re talking in terms of locations where their loved one used to hang out.”

The calls have been fielded at a dedicated phone bank and computer center at the Sheriff’s office. Calls, mostly from the siblings and extended family of young men who vanished in the 1970s.

In 1978, when Gacy’s murder spree was finally discovered, investigators had only dental records and X-rays to identify the victims.

“A family member would come up to people at Gacy’s house and say … ‘I might have a loved one that’s buried down there.’ And they would tell them, ‘Well, we need to get dental records,’” Dart said. “‘Well, you know, my son never had dental problems, he never went to a dentist. We don’t have any.’ ‘Well, ma’am, we won’t be able to do anything.’ And that person would then sometimes walk away.”

Last summer, Sheriff’s investigators exhumed the remains of the eight unidentified Gacy victims and scientists at a Texas lab produced DNA profiles for each one.

Now, family members with years of questions about whether Gacy killed their son can get answers by offering a DNA sample to compare against the victims and the unidentified victims might finally get a name.

“We may not get all eight. That, I think, would be a long shot to get all eight,” Dart said. “I would be very surprised if we don’t get, at minimum, one.”

Dart said one caller was sure that Gacy tried to pick him up while impersonating a cop and only left when a bus came by and scared him off. That caller was convinced he could have been Gacy’s 34th victim.

Dart said he believes the volume of calls might pick up in the days ahead, as families are go though some soul searching and decide to take steps to find out the truth.

But not everyone wants to know.

LISTEN: WBBM Newsradio’s Bob Roberts reports

For more than three decades, some have attached a stigma to being a Gacy victim, even though Gacy was a contractor and many of the boys and young men he strangled simply sought construction jobs — not sex or drugs.

Sheriff’s police spokesman Steve Patterson said that even today, police see evidence that some family members want to know — while others simply want to forget.

“There’s a woman who called and said she hadn’t seen her brother in more than 30 years,” he said. “He did disappear about the time of Gacy’s crimes. He did fit the basic description of Gacy’s other victims. And she said she’d always wondered.”

But Patterson said the subject was taboo in her parents’ household.

Patterson said the woman told him that her father had died, but that her mother remains alive and her attitude is unchanged.

“She doesn’t want to upset her mother, and called asking if just she could come in and get swabbed and not have to say anything,” he said.

Patterson said he told her, “Absolutely.”

Patterson says sheriff’s police detectives merely want to help others find peace of mind. He said that, even if the DNA is not linked to a Gacy victim, it could match samples from other unsolved cases.

Patterson expects the testing to continue well into the new year.

john wayne gacy Sheriff: 25 Legitimate Leads On Unidentified Gacy Victims

Gacy, an ex-convict with a history of sodomy, worked as a contractor on Chicago’s northwest side and northwest suburbs in the years immediately preceding his arrest. He was a Democratic precinct captain and worked as a clown at children’s parties.

Gacy admitted to 33 murders, drawing detectives a map showing where bodies could be found on his property on Summerdale Avenue in unincorporated Norwood Park Township.

He buried his victims in the crawl space beneath his home and elsewhere on the property until he ran out of space, spreading lime atop the bodies beneath his home to aid in their decomposition. He dumped the bodies of his last victims in nearby rivers and streams.
Police moved in on Gacy after he abducted 15-year-old Robert Piest behind a Des Plaines drug store, as Piest’s mother waited for him in front. Piest had gone into the store, where Gacy was doing renovation work, seeking a construction job.

Armed with the map and search warrants, Des Plaines and Sheriff’s Police investigators and evidence technicians systematically tore down Gacy’s house and bulldozed all other improvements on the lot in their search for victims. Another home has since been built on the property.

DNA testing was not available in the 1970s, and evidence technicians and forensic pathologists at the time had to rely on dental records, records of tattoos and other bodily features to try to make identifications.

Authorities are asking the family members of anyone who disappeared between 1970 and 1978 and who is still missing to undergo saliva tests to compare their DNA to that of Gacy’s victims.

Dart has set up a hotline for people to make arrangements for DNA tests: 800-942-1950.

Anyone looking for information also can visit the sheriff’s website by clicking here. The website has general descriptions of the eight unidentified victims and the approximate date those victims would have disappeared.

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