This is the same trick that the Feds pulled at the G 20 protests back in Seattle, the Feds sent paid shills in to pose as anarchists, they come out of the peaceful crowd of protesters smashing windows and throwing rocks and eventually the Police attacked with tear gas, rubber bullets and clubs, the shills are allowed to slip through an area controlled by some of the cops and the other cops go after the peaceful protesters and beat the crap out of them, and then arrest them and put them in a data base. I doubt all the cops knew of the anarchists that were shills.
Then some of the cops went to the University of Pittsburgh and started tear gassing students on film who weren't even protesting, just walking around campus. those cops went after the students who were on their own campus and it's on film on U tube. Jason Bermas was there as a reporter and said he asked some of the supposed cops why they were in military fatigues, they stopped talking to him after he asked.