Police say 19-year-old Shyd Carr-Hanks was arrested on Wednesday and later charged with murder in the shooting death of 16-year-old William Honesty Jr.
Honesty's body was found on the property of Martin Luther King High School back on September 22.
Police say a passerby noticed a body in the grass near the school and called police.
RELATED: 16-year-old dies after being found shot outside Martin Luther King High School in Philadelphia
Officers found Honesty suffering from three gunshot wounds to the chest. He was pronounced dead a short time later.
Officials said the teen was not a student in the School District of Philadelphia, but he lived just over a quarter of a mile away from where police found his body.
The motive for the killing has not been released.
Anyone with information on the case is asked to call police at 215-686-TIPS.
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