ALFRED, Maine (AP) — A judge has sentenced a Maine man to life in prison for brutally killing his grandmother.

Jurors last month found Derek Poulin guilty of murder and arson in the 2012 death of 61-year-old Patricia Noel, who was beaten with a golf club, stabbed about 70 times and set on fire in Old Orchard Beach.

The sentenced was imposed Wednesday in York County Superior Court.

Prosecutors say Poulin was angry because his grandmother asked him to move out. The defense contends investigators focused all their attention on the wrong man and never considered alternative suspects.

The defense says Poulin had a history of mental illness. He was committed to a state psychiatric hospital last year for an evaluation, and the judge ruled him competent to stand trial.