(CBS) — A man was hospitalized after an attack on a Blue Line train in the Loop on Thursday afternoon.

Chicago police say the victim was injured around 2:30 p.m. after an altercation erupted at the Washington Blue Line stop beneath Dearborn Street. The fight then spilled onto a stopping Blue Line train, which never left the station, CTA officials said. A conductor alerted police, who responded.

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Police were looking for four suspects.

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The victim was taken to Northwestern Memorial Hospital. A condition wasn’t available.

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