CHICAGO (CBS) — A man with a valid FOID card and concealed carry license shot another man, who displayed a handgun at the first man, in the Little Village, police said.

Police said around 4:15 p.m. Monday, a 25-year-old man was walking into an alleyway in the 2500 block of South California Avenue. Another man about 20 years old approached the victim and displayed a handgun at him.

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The 25-year-old man produced his own handgun and fired at the other man, shooting him in the head.

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The wounded man was taken to Mount Sinai Hospital in critical condition.

The other man was uninjured and produced a valid FOID card and concealed carry license to officers.

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Area Central Detectives are investigating.