Police announced an investigation after a St. Patrick's Day party took a violent turn in Chester.
Video of the incident went viral, as of Monday morning more than two million people viewed the video which shows a Chester officer striking a young woman.
Police say they responded to reports of a riot Saturday afternoon near Widener University.
Investigators say a violent altercation took place when a group of people forced themselves into a home where a party was taking place.
Soon after police arrived on scene they say 20-year-old Dominique Difiore struck a police officer and was taken into custody.
Police have not confirmed if Difiore is the woman in the viral video. Three other people were also arrested, 21-year-old Shawn Connelly, 20-year-old Tess Herman and 18-year-old Jaylene Westfall.
The Chester Police Department says they are looking into the incident.
“The incident, the video, and level of force used in connection with the event are all currently under investigation,” Chester Police Chief James Nolan wrote in a released statement.
Police are working to determine if anyone else will be charged.