FOND DU LAC COUNTY, Wis. (CBS 58) — Authorities have arrested an 83-year-old man in connection with the 1995 disappearance of James "Jim" Ruland, a case investigators now believe was a homicide.

Jerome P. Baier was arrested at his rural residence near Spencer and is facing a first-degree murder charge in connection with Ruland's disappearance.

James S. Ruland Fond du Lac County Sheriff's Office

Ruland was last confirmed seen on Oct. 24, 1995. A witness later reported potentially seeing him hitchhiking in North Fond du Lac on Oct. 26.

He has not been seen since.

Ruland was 40 years old at the time and was living in Ripon. His vehicle was later found at the Stretch Truck Stop in North Fond du Lac.

Authorities entered Ruland's information into several national databases, including the National Crime Information Center, the National Missing and Unidentified Persons System and the FBI's Violent Criminal Apprehension Program.

Over the past 31 years, investigators have conducted extensive searches for Ruland and his remains.

According to the Fond du Lac County Sheriff's Office, evidence uncovered during the investigation eventually shifted the case from a missing-person investigation to a homicide investigation.

Search efforts have included human remains detection K-9s, ground-penetrating radar, aerial searches, large-scale excavations of possible burial sites, dive teams searching waterways and detectives searching a pig farm manure pit.

In 2021, advances in forensic testing prompted detectives to request additional testing of evidence previously submitted to the Wisconsin State Crime Lab.

Authorities said those results helped corroborate information gathered through interviews and other evidence in the case.

Investigators conducted additional interviews and continued searching for Ruland's remains. Although his remains have not been recovered, authorities said the investigation eventually developed enough probable cause to support an arrest.

Working with the Fond du Lac County District Attorney's Office, detectives obtained a search warrant for Baier's residence.

Baier, who was Ruland's roommate at the time of his disappearance, was taken into custody and transported to the Fond du Lac County Jail.

He remains in custody awaiting his initial court appearance.

"For 31 years, detectives with the Fond du Lac County Sheriff's Office have remained committed to uncovering the truth behind James Ruland's homicide," Sheriff Ryan Waldschmidt said.

Anyone with information related to the case is asked to contact the Fond du Lac County Sheriff's Office.