CHICAGO (CBS) — A man was shot and critically wounded at a gas station in Lawndale Monday afternoon.

The shooting happened at 3:18 p.m. in the 700 block of South Cicero Avenue, right off the Eisenhower Expressway, police said.

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The 22-year-old man was approached by an assailant who took out a gun and fired, police said.

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The victim was struck once in the head and was taken to Stroger Hospital of Cook County in critical condition, police said.

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No one was in custody late Monday afternoon, and Area North detectives were investigating.