The incident happened on the afternoon of July 19 at Frankford Avenue and Levick Street in Philadelphia.
Police say the man "directed racial slurs" at the employee, then got off the bus.
"He's unhappy with the speed in which she opens the doors," says SEPTA Transit Police Chief Thomas Nestel.
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As he was exiting, police say the man threw a can of beer at the bus driver.
The man then displayed a knife and continued "assaultive and threatening behavior," police said.
Earlier this year, video captured a SEPTA employee being assaulted in Center City. Authorities did make arrests in that incident, but Nestel is hoping the transit agency's new YouTube page will tap into a wider audience when it comes to solving these issues.
"We're hoping to reach out to more people, to have contact with more of our riders, employees, and get pictures and videos out to help address some of these problems," said Nestel.
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The suspect in the July 19 case is described as a white male who was wearing a white t-shirt with a blue logo on the front, grey sweatpants, and black shoes. The man has tattoos on both arms and a shamrock tattoo on the back of his left elbow.
Anyone with information is asked to call SEPTA Transit Police at (215) 580-8111. Tips can also be sent by using the SEPTA Transit Watch App or by texting information to (215) 234-1911.
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