Police said the shootout happened during a gathering at Washington Park in the 5100-block South Ellsworth Drive just after 7 p.m.
A male offender of an unknown age was arguing with an off-duty Lyons Police Department sergeant, police said. That's when the offender took out a weapon, and the law enforcement officer identified himself as a sergeant.
Police said both the offender and the off-duty sergeant fired shots.
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The offender, who suffered multiple gunshot wounds, took himself to a local hospital in serious condition, police said. He has been stabilized.
Police said a 46-year-old woman, who was in the park when the gunfire broke out, suffered a gunshot wound to her thigh. She was taken to the University of Chicago Medical Center in good condition.
Area detectives and the Investigative Response Team are investigating. Authorities did not immediately provide further information about the shootout.
The video in the player above is from a previous report.
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