One of John Wayne Gacy's 7 Remaining Unidentified Victims Named, 41 Years After Disappearance

James "Jimmie" Byron Haakenson was just 16 years old when he left his family's Minnesota home for adventure in the summer of '76. He was never seen again.

James “Jimmie” Byron Haakenson was just 16 years old when he left his family’s Minnesota home for adventure in the summer of ‘76.

On Aug. 5, he called his mother to tell her he had made it to Chicago. After that phone call, he was never heard from or seen again.

Four decades later, Jimmie’s family was brought a semblance of closure when authorities confirmed the teen was one of John Wayne Gacy’s unidentified victims, the Cook County Sheriff’s Office said.

The so-called “killer clown” is believed to have murdered at least 33 men between 1972 and 1978, but by the time he was executed by lethal injection in 1994, only 25 of the people he killed had been identified.

The remaining victims were given gravestones that said “We Are Remembered,” but were known by monikers that tied them to the monster that took their lives. Jimmie was Gacy Victim #24.

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Jimmie’s family long suspected he may be one of Gacy’s many victims, and in 1979, his mother tried to confirm whether her son was among the dead.

“Dental records, however, were not available and were the main scientific method at the time to determine if Jimmie was one of the victims,” the Cook County Sheriff’s Office said.

Jimmie’s mother has since passed away, officials said.

Authorities continued to hold out hope that the remaining victims would be given their names back, and in 2011, Sheriff Thomas Dart reopened the investigation.

With the hopes that technological advancements would make developments possible, Dart sent out a request for saliva samples of relatives of men who disappeared between 1970 and Gacy’s arrest in 1978.

“In a way, we’re basically trying to prove someone’s worst nightmare, which is awful,” Dart told The New York Times in 2011. "But the statement we have heard the most from families is that they have been waiting for 30 years to know."

Weeks later, authorities identified the remains of William George Bundy, who disappeared after he left home in October of 1976. He was 19 years old.

"I always knew he was going to be one of them," Bundy's sister, Laura O'Leary, told reporters in 2011. “But without DNA back then, there was nothing I could really do."

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It would be another six years before another person’s remains were identified: Jimmie.

DNA samples collected from Jimmie’s two siblings, as well as detective work that confirmed timelines, led to a positive identification, officials said.

Police made the formal notification to Jimmie’s family on July 17.

“Jimmie was an incredibly special kid,” Dart told reporters. “His family loved him intensely.”

Jimmie’s remains were found in the crawl space beneath Gacy’s home. The bodies of two other men bodies were found in the same grave — Rick Johnston, who was identified at the time of the initial investigation, and Victim #26, whose name remains unknown.

It’s unclear how or when Jimmie and Gacy met, but investigators believe he was murdered at or near the same time as the other victims found in the grave. Johnston was heard from on August 6, one day after Jimmie.

Dart’s reopening of the case also led to the closing of four unrelated cold cases. Investigators also located five missing people alive and two dead, including one teenager who fled an orphanage in 1972, authorities said.

Six of Gacy’s victims remain unidentified.

Anyone who may believe their missing male relative was a Gacy victim is urged to visit the Sherriff’s website for more information.

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