By Asal Rezaei

CHICAGO (CBS) — A CTA bus driver was shot after fighting an unknown offender in Loop on Saturday night.

Police said the driver was physically attacked and then sustained a gun shot wound to the jaw. The shooting happened at Washington Street and Garland around 9 p.m., about one block west of Millennium Park.

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“This incident is absolutely unacceptable,” said CTA President Dorval R. Carter, Jr. on the shooting. “There is no reason the men and women who serve the city should be subject to any kind of attack. These are dedicated public servants who should be able to perform their duties in a safe environment free from this kind of violence.”

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The shooter was arrested shortly after the incident occurred and a weapon was recovered, police said. Charges are pending.

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The 34-year-old driver is in serious condition at Northwestern University Medical Center.