CHICAGO (STMW) – Three people are in custody after allegedly trying to run over police with their vehicle during a traffic stop, then leading officers on a chase that ended Sunday night on the Stevenson Expressway where one officer reportedly shot another in the leg.

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The 37-year-old officer–a 9-year veteran of the force–suffered a gunshot wound to the leg and is expected to fully recover from his injuries, police Supt. Jody Weis said.

Three police sources have said the Ogden District officer was shot by another officer. A Harrison District police source said Harrison District officers did not open fire.

The incident started about 5:30 p.m. at the corner of Polk Street and Francisco Avenue on the West Side when the suspects allegedly tried to use their vehicle to strike Harrison District officers approaching them on foot during a traffic stop, according to the release.

They fled the scene, and Ogden District officers who heard the call on police radio saw the suspects’ vehicle exit the expressway (I-55) at Damen Avenue, according to the release. The vehicle came to a stop after striking a police vehicle.

The officer who was shot was injured when gunfire erupted as officers tried to remove the suspects from the stopped vehicle, the release said. He was being treated Sunday night at John H. Stroger, Jr. Hospital of Cook County.

Independent Police Review Authority spokesman Curtis Tarver said an officer discharged a weapon and an officer was shot, in the area of the Stevenson and Damen Avenue. Carver did not know if the officer who was shot was also the one who had discharged the weapon.

Three suspects in the car were taken into custody, but were not injured in the incident, according to the release.

The officer remains in “critical but stable condition” Sunday night, according to Marisa Kollias, a spokeswoman for Stroger Hospital.

State Police confirmed Chicago Police responded to an incident at that location, but declined to give further details.

Harrison Area detectives and IPRA are investigating.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2010. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. CBS contributed to this report.)

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