Thanks for the link and comments.
On the third video at about 3:50 in, there is a guy who walks up to the seated protestors and pulls out a red bag with something in it- then he hands it to one (or some?) of the protestors. The cops make note of this, and a cop (facing the protestors) walks forward to take it away from the protestor, and he pulls at one of the protestors arms, but the protestor doesn’t give back whatever that object was.
After that, the cop who did the spraying steps over the protestors and starts the spraying.
So, it looks like whatever was handed to the guy (or the perception of a possible dangerous object), and the apparent hiding of that object is what caused the cops to take action, valid or not.
Part 3: http://www.youtube.com/watch?v=NwFa5Kq4Rfo
Good catch - and right before that a guy in black (with a white mask on maybe - that Guy Fookes thing or whatever it is called) also hands a black back to the seated folks in that same section before the red bag is opened.
Those few guys is also where the pepper spray started. You may be correct - the cops saw what they perceived as an escalation and countered it with what they determined to be reasonable force. The sad part is, very few people will see that (I didn’t) and the news will be that “cops spray peaceful protestors”. That plays right into the protestor’s hands - and the media eats it up.
I was hoping that these things would die down, but I think they are too organized for that to happen, and they know the tactics to increase the confrontations. I was also thinking that all of these videos can be used by the cops to review and better their tactics - such as getting surrounded in the first place. I still wonder why they didn’t just take the rest of the people that they had in cuffs out the way they did with the girl.