The alleged incident happened around 12:30 p.m. in the area of the 1200 block of N. Broad Street, between the Erie and Girard Avenue stations.
A SEPTA spokesperson released the following statement:
"That investigation is with the PPD Special Victims Unit. SEPTA police are reviewing surveillance video from the Broad Street Line to assist. We haven't received anything further on a possible location or other details yet."
Philadelphia police have not released any additional information on the incident.
Anyone with any information is asked to call police at 215-686-TIPS.