By Staff

CAMBRIDGE (CBS) — A 19-year-old Boston man pleaded guilty to manslaughter in connection with the death of a 15-year-old girl in Cambridge, the Middlesex District Attorney’s Office announced Thursday. Richelle Robinson was walking to a friend’s house when she was reportedly shoved to the ground on Cambridge Street around 6:30 p.m. on July 22, 2018.

She was found unconscious and bleeding. One day later, she was pronounced dead at Massachusetts General Hospital.

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Isaias Plaza was sentenced to two and a half years in prison with two years to serve and the balance suspended for five years. When he is released, he’ll undergo mental health and substance abuse evaluations and submit to follow-up treatment.

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According to investigators, Richelle and Plaza knew each other and had been in the same friend group before a falling out a few weeks before Richelle’s death.

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“Eyewitnesses informed authorities that they had seen a male, later determined to be Plaza leaving the scene of the assault on a bicycle wearing jeans and black sneakers with white soles. (Then) Plaza later burned the clothes described by witnesses at the time of the assault in an effort to avoid being connected to the death of the victim,” the D.A. said. Staff