This is the following video's description on YouTube:
"This is a video shot the morning of 14 October 2011 as protesters made their victory march around Wall Street. A young man and young woman, who seemed to be unaffiliated with the protests, were being escorted out of the area when the police turned on them, throwing the young man to the ground when he said, 'I didn't do anything! What the f*** did I do?'"
And another video of someone allegedly getting hit by a motorcycle:
Rivera-Pitre getting punched: