By CBS3 Staff

PHILADELPHIA (CBS) — SEPTA says a female porter was attacked on a Broad Street Line platform. It happened Monday morning at the Broad and Walnut station.

SEPTA says she was punched in the face and her head was slammed against a pillar on the platform. The woman reportedly told transit police that she was assaulted by the man after sweeping underneath the bench he was lying on.

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The transit agency says she was transported to Jefferson Hospital for treatment.

The attacker is described as a man in his 20s to early 30s, tall, with medium brown skin, blue jeans, no shoes and a grey heavily worn stretched-out shirt.

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The man fled on Walnut Street toward 15th Street.

No arrests have been made.

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If you recognize the suspect, call SEPTA Transit Police at 215-580-8111.

SEPTA is offering a $1,000 reward for information leading to an arrest.