A man chased two others who robbed his brother's store before he was shot in the head in the Archer Heights neighborhood, police said.
The 36-year-old man who gave chase wasn't armed. Police said his brother's store, in the 4300 block of West 51st Street, was robbed minutes before the chase and shooting.
Two cars were seen chasing each other along Tripp Avenue in the Archer Heights neighborhood and police found a man in one of the cars shot in the head about 8:15 p.m. in the 5400 block of South Komensky Avenue.
The man was taken to an area hospital in critical condition, police said.