A 39-year-old man was found with a stab wound to his upper torso, as police said his 39-year-old roommate was the one responsible.
At the scene, police said they found the victim, 39-year-old Maccarone D. Declements, who had been stabbed in the upper torso with a knife by his roommate.
The roommate, 39-year-old Robert A. Lyon, was still in the house, and authorities placed him under arrest.
Declements was treated for life-threatening injuries and taken to a hospital by air ambulance, police said. Lyon was charged with attempted murder at that time, officials said.
At the hospital, Declements died from his injuries and the charges against Lyon were upgraded to first-degree murder, according to authorities.
Police have not said what caused Lyon to allegedly stab his roommate.
He was booked into the Story County Jail, as the Ames Police Department continues to investigate the incident. Anyone with information is asked to contact the Ames Police Department at (515) 239-5133.