18-year-old pleads guilty to fatally stabbing teen at Long Island house party in 2025

An 18-year-old pleaded guilty Thursday to stabbing a teenager to death on Long Island last year.

It happened on Nov. 3, 2025, at a home on Carlton Road in West Babylon, where police say 90-100 teenagers were gathered for a house party.

According to the Suffolk County District Attorney's Office, Aiden Zachary, of Syosset, tried to get into the party, but he was asked to leave because he didn't have an invitation.

Officials say Zachary, who was 17 at the time, then got into a fight with 15-year-old Liam Delemo, pulled out a knife, and stabbed Delemo in the abdomen and the arm before fleeing.

Delemo's parents told CBS News New York they rushed to the scene after getting a call saying their son had been stabbed. The victim's mother said he was still conscious and alert when they arrived, and he told them, "I love you. I'm sorry."

Delemo was transported to a local hospital, where he died.

Zachary was arrested a week later. He pleaded guilty to first-degree manslaughter Thursday and is due back in court for sentencing on Nov. 4.

"This young defendant chose to escalate a dispute with a deadly weapon, resulting in the tragic death of a 15-year-old boy," District Attorney Raymond Tierney said in a statement. "Two families are now forever changed by this senseless act of violence. My office will continue to hold individuals accountable when they take a life, and I commend my Homicide Bureau for their dedication in securing justice for this young victim."

Delemo's parents said their son was an only child and an 11th grade honor roll student at West Babylon High School.

The homeowner, who police say let her grandchild host the party at her home, was charged with violating the county's social host law and endangering the welfare of a child.