WILKES-BARRE (AP) — A man has been sentenced to 15 to 30 years in prison after pleading guilty in the stabbing death of his grandmother last year in northeastern Pennsylvania.

Eighteen-year-old Eric Montanari Jr. entered the plea Monday to count of third-degree murder. Luzerne County prosecutors withdrew counts of aggravated and simple assault.

He was 17 when 66-year-old Sandra Montanari was stabbed to death March 16 in a home in Weston in Black Creek Township. The victim’s 43-year-old son was stabbed multiple times in the back but was able to call 911.

Montanari apologized in court to more than a dozen family members present. The judge, calling the slaying “senseless,” barred him from contact with family unless they choose to contact him. He was credited with 319 days already served.