Police say three people have been wounded, two critically, in a shooting at a Chicago Transit Authority train stop.

Chicago Police Department spokeswoman Amina Greer says the shooting occurred on the mezzanine level of a Red Line "El" station on the city's South Side.

She says a 25-year-old man and a 41-year-old woman were shot and taken to a hospital in critical condition. A third victim, a 24-year-old man, sustained wounds to his face from glass fragments. He was hospitalized in stable condition.

Greer says preliminary information indicates that the female victim was arguing at the station with an acquaintance, who produced a gun and fired shots.

No one is in custody.

There was no service interruption for the CTA.