The incident occurred shortly after 5 a.m. on Tuesday, February 8, on the southbound platform of the North Philadelphia Station on the Broad Street Line.
According to police, the man exposed himself to a woman and performed a lewd act on the station's platform.
Officials say the man then boarded a southbound train afterward.
Anyone with information about the man is asked to contact SEPTA Transit Police at (215) 580-8111.
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