50 years after a hitchhiker was murdered in Wisconsin, an 84-year-old man is arrested for her death

An 84-year-old man was arrested this week in connection with the murder of a female hitchhiker 50 years ago in Wisconsin.

Mary K. Schlais, 25, was found dead at an intersection in Spring Brook, Wisconsin, on February 15, 1974. Dunn County Sheriff’s Office said.

The Minneapolis woman was killed while hitchhiking to an art exhibit in Chicago, Sheriff Kevin Bygd said Friday.

“This was a very smart lady who had a very bright future ahead of her,” he said. “Her life was taken from her.”

Although investigators worked on the case for decades, seeking tips and gathering evidence, “no viable suspects were identified,” the sheriff’s office said.

But through forensic genetic genealogy, Bygd said, investigators tracked down Jon Miller, 84, to his apartment in Owatonna, Minnesota. Miller confirmed his involvement in Mary’s murder after 50 years on Thursday, Bygd said.

Miller was awaiting extradition to Wisconsin, Bygd said. It was not clear Friday afternoon whether Miller had retained an attorney.

Bygd said he was ecstatic when he heard of Miller’s arrest.

“I had trouble controlling my excitement,” he said. “You know, I’ve been here at this agency for 35 years and this case has been in the works for all of those 35 years.”

The sheriff continued, “This is a huge victory for our agency.”

The sheriff’s office said it had worked with Ramapo College in Mahwah, New Jersey, in recent years and its team of genetic genealogists helped identify Miller as a suspect.

Through genetic genealogy, law enforcement uses commercial DNA databases to find family matches to the DNA of a crime suspect, victim or missing person.

Last month, authorities in Arizona announced they were using genetic genealogy to identify a John Doe whose remains were found near the Hoover Dam more than a decade ago. The man was not seen by his family for almost thirty years.

Don Schlais, 79, of Minneapolis, said Friday he never thought he would see the day an arrest would be made in his sister’s death.

“It’s just surreal. You don’t expect it after all this time,” he said.

Schlais said his sister earned a bachelor’s degree in art from the University of Minnesota and was applying to graduate school. She was passionate about horses and riding, he said.

Schlais blamed the police and forensic team for the arrest. He said whatever happens to Miller is out of his control.

“I’m going to let go and I’m going to let God,” he said. “I suspect he will take care of this. He will have to pay the karma when he dies.

This article was originally published on NBCNews.com