They released surveillance images of the suspects earlier Wednesday.
Surveillance images released of Argyle Red Line shooting suspect
Police said the two men walked onto the station's platform at about 4 p.m. Monday and specifically targeted two other men at the station and shot them.
A 41-year-old victim suffered a graze wound to his thigh, while a 34-year-old man was shot multiple times in the abdomen and back.
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Police said one of the suspects was wearing a black Adidas jacket with white stripes on the sleeves and dark ripped jeans and green shoes. The second suspect had short dreads and was wearing a light-colored Tommy Hilfiger hooded jacket, blue pants with white stripes on the side and white and black gym shoes.
Anyone with information is asked to contact Area North Detectives at (312) 744-8261.