After nearly four decades on the run, Walter James Mason, 86, has been arrested in connection with a decades-old murder case.

Mason was discovered in central Texas by East County Sheriff’s deputies living under the alias Walter James Allison, according to sheriff's deputies in Idaho, where the killing happened nearly 40 years ago.

It was September 22, 1980, when the Custer County Sheriff's Office was called to the Sport’s Club bar in Clayton, Idaho, where they discovered Daniel Mason Woolley dead from a gunshot to the head. Another male bar patron had been shot in the shoulder and a female injured by “blunt force to her face,” police say.

Mason, who lived and worked in the area, was the primary suspect in the murder, according to the police. The Custer County Sheriff's Office, FBI and the Idaho Department of Fish and Game attempted to track Mason down but he eluded them.

Decades later, on October 10, Mason was located and his identify confirmed by matching his fingerprints, the sheriff's office said.

On October 13, two members of the Custer County Sheriff's Office transported Mason back to Idaho, where he awaits trial for murder in the first degree. He is being held in a secure detention facility, according to the sheriff's office.

David Cannon was retained as Mason's public defender, and Mason has pleaded not guilty. Cannon did not return a call requesting comment. (CNN)

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