An autopsy has found that a psychiatric nurse at a California mental hospital was strangled.
Authorities suspect 54-year-old Donna Gross was killed Saturday by a mentally ill patient in the courtyard at Napa State Hospital.
The Napa County coroner's office said Tuesday that Gross died of asphyxiation.
Jess Willard Massey was arrested Sunday for investigation of murder and robbery and is expected to make his first court appearance Tuesday.