By Charlie De Mar

(CBS) – He jumped in to try and help a woman getting attacked on the CTA Red Line.

His quick thinking led to an arrest, but he is also paying a price. CBS 2’s Charlie De Mar reports.

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Marvin Smith was on his way to work in December when he saw a disturbance on the train he was riding.

A teenage boy and an adult woman were arguing.

“Everyone started covering their faces, people started coughing,” Smith says.

Police say the 16-year-old got physical with the woman, 23, and she pepper-sprayed  him.

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When the teen tried running for the exit at North and Clybourn, Smith stepped in. He got pushed into a wall and nearly blacked out.

“I had a brain bleed. I had facial fractures I’ve had some teeth fractures,” Smith tells De Mar.

The teen was caught and charged with two counts of aggravated battery.

Smith, meantime, has a long road to recovery and dental bills are adding up fast. A Go Fund Me page has been started to help with some of the costs.

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He says regardless, he doesn’t regret getting involved.

Charlie De Mar