Philadelphia police are investigating a video that appears to show a police supervisor striking a Puerto Rican Day parade reveler in the head, sending the woman to the ground before she was charged with disorderly conduct.

According to a YouTube video posted Sunday, several parade-goers can be seen spraying water on the street and on a throng of police officers before a police supervisor zeroes in on the unidentified woman as she tries to walk away from the group.

The officer is then seen striking the woman in the face and to the back of her head. She is later led away in handcuffs.

Lt. Ray Evers, a Philadelphia Police Department spokesman, told the Philadelphia Daily News police officials are “fully aware” of the video and that an Internal Affairs investigation has been opened. Police Commissioner Charles Ramsey, who is in San Diego for a conference, is also aware of the video, Evers said.

The 36-second video — titled “Philadelphia Police Brutality” — has been viewed more than 300 times as of midday Monday. It is not clear what happened prior to the recorded sequence.

The 39-year-old woman, who was not identified, was issued a disorderly conduct citation. Evers said the woman’s citation indicates "liquid and some other objects were thrown at a group of officers causing a large crowd. She was the only person charged in the incident, he said.

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