By CBS3 Staff

PHILADELPHIA (CBS) — A former SEPTA guard caught on surveillance video punching a customer is now facing aggravated assault charges. Police arrested Dashaun Young on Monday.

Eyewitness News first showed you the surveillance video last month.

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Police say Young knocked a man to the ground and then repeatedly punched him at the Arrott Transportation Center.

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At the time, a SEPTA spokesperson said there was some sort of argument that turned physical.

“It appears the two were in a verbal disagreement of some type for a couple minutes before it became physical. And then the video shows that the security guard struck the man and the man fell to the ground,” SEPTA spokesperson Andrew Busch said.

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Young worked as a private security guard for Allied Universal and we’re told he’s been fired from his job.