CHICAGO (CBS) — A U.S. postal worker was shot with a paintball gun Friday morning, while delivering mail in the Ashburn neighborhood on the South Side.

Police said the 65-year-old postal worker was delivering mail near 76th and Springfield around 10:30 a.m., when he heard what sounded like a shooting, and noticed blue paint on his pants and a bruise on his right calf.

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The victim told police he saw a small dark vehicle driving south on Springfield at the time.

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Police did not have a description of the person who fired the paintball gun.

The postal worker declined medical treatment.

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Area Central detectives were investigating.