The shooting took place at about 3:06 a.m. in the 10600-block of South La Salle Street.
Officers responded to a report of a domestic disturbance. Police said an off-duty officer was in the basement of the residence when he was alerted to the domestic disturbance and went upstairs.
Police said the off-duty officer got into a confrontation with the suspect and the officer fired his weapon and wounded the suspect.
The suspect was wounded and transported in critical condition to Advocate Christ Hospital, police said.
No other injuries were reported and two guns were recovered from the scene.
The Investigative Response Team and the Civilian Office of Police Accountability are investigating the shooting. The officer involved will be placed on administrative duties for a minimum period of 30 days.
COPA is also investigating a separate shooting involving an on-duty officer in the Grand Crossing neighborhood Monday morning.
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