The Civilian Office of Police Accountability is investigating Saturday morning after a shootout between two people and an off-duty Chicago police officer in South Loop. The shooting happened just before 4 a.

An off-duty police officer was shot at and returned fire on a suspect in the South Loop, the Civilian Office of Accountability reported. Around 3:45 a.m., the officer said she saw two suspects approach a 25-year-old man on a sidewalk near the 100 block of West Polk Street.

An investigation has been launched following an off-duty officer-involved shooting in South Loop early Saturday morning.

A man, 25, was on the sidewalk in the first block of West Polk Street at 3:45 a.m. when two people approached him, police said. A woman, a 25-year-old off-duty CPD officer, approached the group in a car and one of the two people who had approached the man on the sidewalk shot at her before she

The shooters left the scene in an unknown direction, police said. No one was hit by the gunfire, and as of Saturday, no arrests were made.

An investigation by Chicago’s Civilian Office of Police Accountability (COPA) is underway after an off-duty officer was involved in a shootout in the South Loop early Saturday morning. WGN's Emmy Victor has the latest developments.