CHICAGO (CBS) — A man was shot while he was riding in a vehicle on the Eisenhower Expressway early Saturday on the West Side.

The man, whose exact age was unknown, was sleeping in a rear seat of a vehicle about 4:30 a.m. as it drove west on I-290 near Racine Avenue, according to Illinois State Police.

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Someone in another vehicle on the expressway fired shots at the vehicle he was inside and he was struck in the knee, police said.

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The driver took the man to Rush University Medical Center, where he was treated for a gunshot wound that was not life-threatening, police said.

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