This is the shocking moment a police sergeant punched a young woman in the face because he thought she sprayed silly string at him during a peaceful parade. The video was recorded during yesterday's 50th anniversary Puerto Rican Day parade in Philadelphia - where around 1,500 people were in attendance. The 36-second clip shows a number of people milling around enjoying the festivities in the 'City of Brotherly Love'. From the left-hand side, someone can be seen throwing an unidentified liquid towards a group of police officers. At the same time, a young woman is walking past - who also...