Woman who hitchhiked in the snow was murdered in 1974. Fifty years later, police say they have arrested her killer

Fifty years after the murder case against a 24-year-old woman went unsolved, authorities say they have identified her killer.

Mary K Schlais was stabbed to death on February 15, 1974, while allegedly hitchhiking from Minneapolis to Chicago for an art exhibition. Now, five decades later, the Dunn County Sheriff’s Office arrested Jon Keith Miller, 84, for her murder.

Investigators found Miller based on genetic evidence — a hair found on a hat — left at the crime scene, according to the criminal complaint seen by CBS News. The hat belonged to Miller, he told investigators.

After tracking him down to his apartment in Owatonna, Minnesota, police interviewed Miller, who “confirmed his involvement in Mary’s 1974 murder,” the sheriff said.

Miller admitted to picking up the young hitchhiker and asking for “sexual contact,” according to the complaint. She refused his advances, prompting him to grab a knife in the car and fatally stab her in the back.

Schlais was found dead with multiple stab wounds. But the murder weapon has not yet been recovered, Sheriff Kevin Bygd said at a news conference.

He faces one count of first-degree murder, records show. The 84-year-old is being held in Steele County, Minnesota and awaits extradition to Dunn County later on Friday.

“In 1974, it wasn’t that unusual for someone to hitchhike from Minneapolis to Chicago. But it’s stories like this that are the reason we don’t let our kids do this anymore,” Bygd said. “This was a very smart young lady who had a very bright future ahead of her, and her life was taken way too young.”