It should be noted that none of this took place until protestors had already been 'kettled' (held by police in a relatively confined external space with no access to external food, water, medication, sanitation, etc, and no way out, even for the unwell, disabled, etc) for several hours, after already being constantly intimidated by the police, who repeatedly assembled in riot gear and formed lines as if they were planning on baton charging them while they were eating cake and dancing to samba. Not an object had been thrown, not a window smashed, not a person hurt, yet they were kettled despite their non-violence.
So people reading this and thinking that there were violent people running amok in climate camp, please understand that this is what happens when you back people into a corner and hold them hostage for protracted periods of time, and I'm sure that if you felt the same frustration, you would be just as angry.