CHICAGO (CBS) — Riders on a CTA bus got a bit of a scare Wednesday morning when a gun accidentally went off after a passenger picked up a small pistol he found on the bus.

WBBM Newsradio’s Bernie Tafoya reports CTA officials initially said an unattended handgun fell off a seat on a #47 bus near the intersection of 47th Street and Kildare Avenue, and went off when it hit the floor.

However, Chicago police later said a 45-year-old man who was riding the bus picked up the gun from the seat, thinking it was a toy or a lighter shaped like a gun. He quickly discovered his mistake when the gun accidentally went off, and the bullet struck a piece of metal on the bus.

A woman on the bus felt something strike her thigh — either a fragment of the bullet, or flying debris — but it didn’t even pierce her clothing.

The woman declined an offer from paramedics to take her to the hospital.

Police said the man who picked up the gun would not face charges, as it was an accident.

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