WEST BABYLON, NY — A Syosset teenager pleaded guilty Thursday to fatally stabbing a 15-year-old boy during a house party in West Babylon last year, Suffolk County District Attorney Ray Tierney said.
Aiden Zachary, 18, pleaded guilty to first-degree manslaughter in connection with the November 2025 death of Liam Delemo, 15, of West Babylon, prosecutors said.
According to court documents and Zachary's admissions during his guilty plea, Zachary, who was 17 at the time, arrived uninvited at a large house party in West Babylon and was asked to leave.
An altercation broke out between Zachary and Delemo, prosecutors said.
Moments later, Zachary pulled out a knife and stabbed Delemo in the abdomen and arm before fleeing the scene, according to the district attorney's office.
Delemo was rushed to Good Samaritan Hospital in West Islip, where he was pronounced dead, authorities said.
Police previously reported that between 90 and 100 teenagers were gathered outside a home at 813 Carlton Road when the deadly altercation occurred.
Zachary was arrested on Nov. 10, 2025, and initially charged with second-degree murder.
Zachary pleaded guilty Thursday before Acting Supreme Court Justice Karen Kerr to first-degree manslaughter, a class B violent felony.
He is scheduled to return to court Nov. 4 for sentencing, prosecutors said.
Zachary is represented by attorney Jacon Kaplan, who was not immediately available to comment.
"This young defendant chose to escalate a dispute with a deadly weapon, resulting in the tragic death of a 15-year-old boy," Tierney said. "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."
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