According to investigators, the male suspect and victim got into a fight around 12 p.m. on the southbound platform of the Broad Street Line near North Broad Street.
The victim was stabbed once in the neck and taken to an area hospital for non-life-threatening injuries.
Police say the suspect fled through the tracks and exited at the Cecil B. Moore Station.
Anyone with information should immediately call SEPTA police at (215) 580-8111 or call 911.
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