CHICAGO (CBS) — A man was struck by a stray bullet and critically injured late Thursday on a Green Line train in the Washington Park neighborhood.

At 6 p.m., the 22-year-old man was on sitting on the Chicago Transit Authority Green Line train at the 51st Street stop when he was struck in the back of the neck by a bullet, police said.

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First he heard the gunshot, then he found out he was hit in the back of the neck.

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The bullet was a stray bullet and the man was not the intended target, police said.

He was taken to the University of Chicago Medical Center in critical condition.

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Area Two detectives were investigating Thursday evening.

CBS 2 Chicago Staff