OWATONNA, Minn. — An 84-year-old southern Minnesota man has been charged with murder in a 50-year-old case in Wisconsin once believed to be the work of a notorious serial killer and former Green Bay Packer.

On Feb. 15, 1974, Mary K. Schlais was found dead at an intersection in Spring Brook Township, Dunn County, according to the sheriff’s office. Police declared it a homicide.

Schlais was from Minneapolis and police believe she was hitchhiking to Chicago for an art exhibit.

Decades passed as investigators pursued leads, conducted interviews and examined evidence. The Dunn County Sheriff’s Office said it used DNA evidence to find and arrest Jon Miller of Owatonna.

Authorities charged Miller with first-degree murder Thursday, according to court records. He is in custody and awaiting extradition to Wisconsin.

How authorities identified Miller as a suspect

Charges filed Thursday say investigators found a beanie near Schlais’ body in 1974 and recovered hairs from it.

Years later, researchers used the hair to create a DNA profile of the suspect. Dunn County has partnered with Ramapo College in New Jersey, which specializes in genetic geneology. After interviewing and collecting DNA from several potential relatives, authorities were led to Miller, the criminal complaint states.

Before speaking to Miller, authorities went to her daughter’s home and received her genetic profile. Research indicated that the hair in the bonnet belonged to her biological father. Investigators say the fact that Miller was initially adopted made it more difficult to track him down.

On Thursday, investigators met with Miller, who initially denied any knowledge of Schlais’ murder. When told about the DNA evidence, Miller admitted to picking up Schlais while she was hitchhiking and asking for “sexual contact,” the complaint states.

He reportedly told investigators that when she said no, he grabbed a knife he had stored in the car and fatally stabbed her in the back.

Schlais had multiple stab wounds when she was found dead, according to the complaint, including defensive wounds to her hands.

According to the complaint, Miller said he drove off the highway and tried to hide Schlais’ body in a snowbank, but became frightened when a car drove by and left the area.

Miller also admitted that the beanie found at the scene was his, according to the complaint. He was arrested following an interview with investigators and is being held at the Steele County Jail.

“We were sitting at the kitchen table last night and we got a call,” said Mary Dodge, who lives with her husband Jack near the wooded spot where investigators found Schlais’ body. Their neighbor Denny Anderson was driving near Miller when he allegedly left Schlais’ body in the snow, and he alerted authorities.

“Denny said when he walked by, the guy was just looking at him. He said he’d never forget the look on his face,” Mary Dodge said.

Previous suspect was accused of serial killer, former Green Bay Packer

In 2009, Schlais’ body was exhumed, and DNA testing allowed investigators to identify a suspect two years later: Randall Woodfield, a former Green Bay Packers draft pick who would later become known as killer I-5.

Authorities linked Woodfield to dozens of murders along Interstate 5, from Washington to California, in the 1980s. He is in prison for one murder, but has never confessed to any of the killings.

Woodfield was traveling from Portland to Green Bay at the time of Schlais’ killing, authorities determined, and he matched a witness’ suspicious description. Woodfield was never further linked to or charged with Schlais’ murder.

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