CHICAGO (CBS) — A Red Line train was evacuated, and CTA trains bypassed the Addison ‘L’ station for nearly three hours Thursday morning, after passengers reported seeing a white powdery substance on the train.

Police said the train and the Addison platform were evacuated around 8:30 a.m., as part of a hazardous materials response by the Police Department and Fire Department.

The CTA said a white powdery substance was reported on a southbound Red Line train, and passengers were evacuated.

A passenger who was on that train said a woman hit the button to speak to the driver, after she noticed a man spill what looked like a white powdery substance, and then hop off the train and onto a northbound train.

“She seemed really concerned about it,” Shawn Cassellius said. “The next thing I know, the train driver is saying everybody has to get off the train, and shortly after a couple minutes overheard that everyone needed to evacuate the station.”

CTA officials confirmed a white powder was found on the train, but have not determined what the substance is.

The CTA said normal service on the Red Line had resumed by 11:15 a.m.

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