I was there last night. Didn't see the drone, but I did see some cops on Segway's with video camera's taping the crowd.
Looks like a Phantom 2 to me.
Probably civilian. It's not cool to throw things at quads with the intent to bring them down, especially not near a crowd of people.
If it was civilian, they have every right to be there, just like the countless other cameras and photographers in the area. It's expensive equipment that people shouldn't be excited about destroying.