Video of a policeman spraying demonstrators yesterday was posted on YouTube.
Protestors have complained that police used excessive force in trying to contain the crowd that marched from Zuccotti Park near the New York Stock Exchange to Union Square.
Police say about 80 people were arrested, and most were taken into custody for illegally blocking traffic.
Their charges include disorderly conduct, resisting arrest, and in one instance, assaulting a police officer.
Police say the street protest was illegal as the crowd did not have a permit.
Still, many protesters claim the officers used excessive force.
"Officers started taking people who were saying the wrong things or too close to the barricades and just pulling them aside and beating them," said a protester. "And if they resisted arrest in any way, if you did not put your hands right behind your back, they kicked you in the stomach and six officers jumped on top of you and started arresting you as roughly as they could."
"What happened today was unfortunate. But we were being peaceful, nonviolent," said another protester.
“[The officer] grabbed me by my belt and the back of my pants and threw me over a bench," said a third.
Demonstrators are gathering again today in Lower Manhattan for their ninth day of demonstration to protest issues including what they call Wall Street's "close relationship" with Washington.
The NYPD will remain a strong presence by the ongoing protests.