NORTHAMPTON, Mass. (AP) — An autistic Massachusetts man has pleaded guilty to charges he repeatedly stabbed his mother in 2015.

The Northwestern District Attorney's Office says 22-year-old Zachary Holmes, of Belchertown, was sentenced Monday in Hampshire Superior Court to 293 days in jail, which he has already served, and five years of probation.

Holmes pleaded guilty to assault and battery with a dangerous weapon stemming from the September 3, 2015 attack.

His mother, Joann Holmes, has said that her son suffered a "psychotic break" when he attacked her and should not face charges.

Northwestern District Attorney Mary Carey says Holmes was deemed competent to stand trial despite his autism. Carey says the state is obligated to protect victims even when they disagree.

Holmes now lives in a supervised apartment in Amherst.