The boy has been charged with first-degree murder and attempted first-degree murder.
CPD said on Oct. 22, the boy was the third suspect who shot and killed Devajae Christopher, 16, and Tamarion Hakeem West, 17, in the 8100-block of South Marshfield Avenue in Gresham.
A 21-year-old man was seriously injured in the same shooting.
The boy was arrested Monday in Chicago.
Omarion Roberson, 19, and Jarvis Bell, 32, were previously arrested for the shooting.
Both are also facing first-degree murder and attempted murder charges.
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