CHICAGO (CBS) — A man suffered a cut to his left arm Wednesday morning when another passenger on a Red Line train stabbed him near the Cermak-Chinatown stop.

Police said around 8:30 a.m., officers responded to a call of a person with a knife at the Cermak-Chinatown stop on the Red Line.

When officers arrived, a 28-year-old man told police another man had approached him on a Red Line train, yelling that he knew him. The man then pulled out a pair of scissors and stabbed the victim, causing a laceration to his left arm.

The victim told police he did not know his attacker.

The victim was taken to Mercy Hospital & Medical Center for treatment.

Police said the attacker is in custody.