Billings police on Tuesday identified Beau Papin as the man arrested on suspicion of killing his mother.
Police said Papin, 20 years old, was arrested Monday afternoon shortly after officers were called to a residence at 143 Calhoun Lane for a report of a disturbance.
When officers arrived they found the body of a 41-year-old woman in the living room "with injuries consistent with a cutting instrument," Lt. Brandon Wooley said in a news release on Tuesday.
Papin was arrested a couple hours later when he returned to the scene, Wooley said. He is being held in the Yellowstone County jail on suspicion of deliberate homicide. He has yet to make his first court appearance.
The Yellowstone County Coroner's Office has identified the woman as Jessica Papin; coroner Cliff Mahoney said Papin died of multiple stab wounds.