That same year, Clark received a separate 3 1/2 to 7-year sentence for robbing three men at gunpoint. The Inquirer reported that he was also charged in 2009 with breaking into his wife's apartment and threatening to kill her, but the case was dropped for "lack of prosecution."
Clark's alleged attack of an unsuspecting woman at the Chinatown station of the Broad-Ridge Spur at 8th and Race streets this week was captured by a surveillance camera.
SEPTA police Chief Thomas Nestel said the victim, whom they didn't identify, told investigators that Clark asked her for a light and that she handed it to him.
"He returned it, and then he hauled off and just starting hitting her," Nestel said. "It was horrifying."
The recording shows Clark allegedly dragging the woman from a bench by the legs and tossing her like a rag doll to the tracks below the station platform.
SEPTA police arrested Clark on Thursday afternoon near 15th Street and John F. Kennedy Boulevard.
The Chinatown station is one of the least-used in SEPTA's network. Over the course of about an hour on Friday afternoon, fewer than a dozen people passed through the cold, drafty station, where the buzz of generators stood in for the lack of activity.
Nestel said the attack appeared to be the random work of a possibly mentally ill individual.
"Today is no different than next Thursday or three Saturdays from now - you should always be aware of your surroundings," he said.
Nestel added that riders who spot suspicious activity should contact SEPTA police at 215-580-8111.
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