RUTLAND, Vt. — A Vermont man who told police he attacked and killed his 82-year-old mother because he believed she was possessed by Satan has been sentenced to eight to 15 years in prison.

The Rutland Herald reports 55-year-old Roderick Geronimo was sentenced Tuesday after pleading guilty to manslaughter in July in the 2012 death of his mother, Gertrudes Alwardt. The East Poultney resident said no one was more sorry for her loss than he was.

Police say Geronimo pushed a table into her and hit her over the head with wine decanters before pouring water into her mouth to “cast the devil out.”

Alwardt died of blunt force trauma to the head and torso.

The defense and prosecution said Geronimo was suffering a psychotic episode at the time, and his charge was reduced from murder.