A 23-year-old man was shot Monday afternoon after boarding a Red Line train at the Garfield station on the South Side.

About 2 p.m., the man got into an argument with someone at a turnstile at the station, 220 W. Garfield Blvd., that continued when they walked to the platform, according to Chicago Police. After they both boarded a train, the suspect pulled out a gun and shot the man in his shoulder. The shooter then got off the train and took off.

The man was taken to University of Chicago Medical Center, where his condition stabilized, police said.

No one was in custody immediately following the shooting.

Normal service on the Red Line was restored shortly after 3 p.m.