WARNING GRAPHIC CONTENT: An off-duty Cook County Sheriff's sergeant shot and killed a man who tried to rob him Monday night at a Far South Side gas station. (Posted on: February 11, 2014)

An off-duty Cook County Sheriff’s sergeant shot and killed a man who tried to rob him Monday night at a Far South Side gas station, police said.

The shooting happened shortly before 10 p.m. on the 700 block of East 103rd Street in the Pullman neighborhood, officials said.

The sergeant stopped on his way home at a Citgo station on 103rd Street and Cottage Grove Avenue across the street from Gately stadium and was approached by as many as three men, a law enforcement source said, citing preliminary information.

Police News Affairs Officer Hector Alfaro said the robbers had demanded the sergeant’s wallet. But when the sergeant complied, the armed robber pointed his gun in the sergeant's direction. In response, the sergeant shot the robber in the head, said Alfaro, citing preliminary information.

That robber's gun was found at the scene and the off-duty sergeant was not hurt. Chicago police are trying to find the other suspects, who fled the scene.

In a statement, Cook County Sheriff's office spokesman Benjamin Breit said it appears the sergeant was the intended victim of a crime and shot someone while acting in self-defense.

The Cook County medical examiner's office said this morning that the deceased man is believed to be in his 30s, but as of 5:40 a.m., he has not been identified.

Earlier Monday, another man was shot in his ankle about 7:25 p.m. on the 5800 block of South Princeton Avenue in the Englewood neighborhood, Alfaro said.

The man was taken to Saint Bernard Hospital and Health Care Center, he said.

dawilliams@tribune.com

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