CHICAGO (CBS) — Cook County Sheriff Tom Dart announced Monday that his office has identified another victim of notorious serial killer John Wayne Gacy: Francis Wayne Alexander, of North Carolina.

Dart said Alexander likely was killed by Gacy between early 1976 and early 1977, and would have been 21 or 22 years old at the time of his murder.

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The sheriff said Alexander was born in North Carolina, and his family later moved to New York, where he got married, before moving to Chicago in 1975. He later got divorced and then disappeared, according to Dart.

“He had both the misfortune of living in the area where John Wayne Gacy did most of his killing, where he targeted most of his victims. He also had the misfortune of also operating in an area where John Gacy targeted specific people and specific groups as well,” Dart said.

Francis Wayne Alexander (Source: Cook County Sheriff)

Dart said Alexander’s family at the time believed he simply wanted to be left alone, and no missing person’s report was ever filed.

“It is hard, even 45 years later, to know the fate of our beloved Wayne. He was killed at the hands of a violent and evil man. Our hearts are heavy. Our sympathies go out to other victims’ families. Our only comfort is knowing this killer no longer breathes the same air as we do. We can now lay to rest what happened, and move forward by honoring Wayne. We ask that you respect our wishes of privacy as we process this tragedy,” his family said in a statement provided by Dart’s office.

DNA from one of Alexander’s molars was used to identify him.

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Cairenn Binder, a forensic genealogist with the DNA Doe Project, a non-profit group that works to help identify John and Jane Does through genetic testing, said they were able to match the DNA from Alexander’s molar to several members of his family tree on a genealogy website, including his second cousin and several other more distant cousins.

The DNA Doe Project then shared those DNA samples with Dart’s office, who were able to complete the investigation and determine Alexander was the Gacy victim previously known only as Victim Number 5, by comparing the DNA from Alexander’s tooth to his mother’s and half-brother’s DNA.

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Sheriff’s detectives also used financial records, parking tickets, and other records to confirm Alexander was Victim Number 5.

“It was the typical painstaking work of finding out when Wayne was last seen – tax records, parking tickets – that we were able to put this all together, combining it with the DNA,” Dart said.

Dart said he spoke to Alexander’s family after identifying him as one of Gacy’s victims, and they are “incredibly thankful” to have a sense of closure.

“I’m ecstatic we were able to bring out some closure. It’s heartbreaking talking to the family. This is the first time we actually had a parent that was still alive from one of the cases, and it was very difficult talking to her; a very, very sweet, sweet lady,” Dart said.

Gacy killed at least 33 young men in the 1970s. Most of the victims were buried in Gacy’s home crawlspace.

For more than a decade, Dart’s office has been working to identify previously unidentified victims of Gacy’s killing spree, using new DNA testing technology.

In 2011, detectives used DNA to confirm that 19-year-old William George Bundy was one of Gacy’s unidentified victims. He was a Senn High School dropout who disappeared in 1976.

In 2017, the sheriff’s office identified 16-year-old James Byron Haakenson, a runaway from Minnesota, as another Gacy victim.

Five other victims remain unidentified, and Dart said his office is committed to continuing its work to find out who they were.

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“We are going to continue pressing ahead with that. We’re going to utilize all these different tools that we have utilized on this,” he said.

CBS 2 Chicago Staff