CHICAGO (CBS) — Police are investigating after a woman was stabbed in the shoulder and wounded while riding a CTA Red Line train on the city’s South Side.

Around 9:20 p.m. Wednesday, the woman was riding a southbound Dan Ryan branch Red Line train near the Sox-35th Street station, when she was stabbed in the shoulder, police said.

A fight had broken out on the train, Chicago Transit Authority spokeswoman Wanda Taylor said. Police were called, but by the time they arrived, those involved in the fight had left, she said.

Still, the woman was taken to Mercy Medical Center in good condition for her injuries, police said.

Taylor said the train was taken out of service and turned over to police.

Police were recovering evidence from the train after it was transferred to the 95th Street station, according to unconfirmed police dispatch reports.

It is unclear whether the woman knew her offender, but no one was reported in custody Thursday morning.

The Sun-Times Media Wire contributed to this report.

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