Officers arrested Luis Suarez-Vasquez in Markham on Wednesday.
He allegedly participated in the fatal shooting of another 18-year-old man on June 14 in the Back of the Yards neighborhood's 1700-block of West Garfield Boulevard.
In the same incident, police said, Suarez-Vasquez robbed a 17-year-old boy and a 19-year-old woman at gunpoint alongside a 33-year-old man. He is accused of holding all three without their consent.
Suarez-Vasquez faces one count of first-degree murder, two counts of armed robbery with a firearm, and three counts of kidnapping. He is due in court on Friday.
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