The shooting happened in the 1200 block of Dante Avenue, the Dolton Police Department said. One or two masked offenders entered the gymnasium, which is part of New Life Celebration of God church's campus, and opened fire.
WATCH: Police provide update after deadly gym shooting
1 killed, another hurt in shooting at south suburban gym, police say
The medical examiner later identified the man killed as 30-year-old Marcus Stevens.
Another person suffered a minor laceration while trying to get away, police said. They are being treated at a local hospital.
Police said they do not believe the shooting was random. There is no one in custody and police are investigating.
Police did not provide further information about the shooting.
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