It happened at the convenience store on Race and Broad streets.
According to police, the employee was stabbed under his armpit during a robbery.
The employee was rushed to Jefferson Hospital, where he is listed in critical condition.
Investigators say there were multiple witnesses inside the store when the incident occurred. They reportedly described the suspect as 6'1" tall and wearing a blue shirt and shorts.
SEPTA police say they were later able to stop a male suspect at 15th and Market streets who fit the description.
A witness from the robbery allegedly identified the suspect as the robber.
The suspect's identity has not been released. No further information has been released on the incident.
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