One of the teens involved in the fatal stabbing of Barnard University student Tessa Majors late last year has been sentenced to 18 months in juvenile detention after reaching a plea deal with prosecutors that allowed him to avoid a murder charge, NBC New York reports. Under the plea deal, the 13-year-old was charged as a minor, and he will spend at least six months in custody before New York City’s children’s services department can decide whether he should be released. The teen has insisted he was not “the main actor” in the stabbing of Majors in Morningside Park, which authorities have described as a “robbery gone wrong.” Two other teens allegedly involved have pleaded not guilty to second-degree murder and robbery.

In a statement, prosecutor James Johnson said Majors “was a bright, promising, and talented young woman who had just begun to explore life as a college student in New York City when she was tragically and senselessly murdered.” “While we have brought this portion of this horrific case to a close, we know that the pain of this loss will endure,” he added.