I clarified in my other comment -- I wasn't trying to imply that the violence here was a consequence of the extremists involved having any legitimate claim that their free speech has been curtailed.

I think this riot is best understood as being actively organized by the current ruling party.

I think there is a clear free speech issue in the current politics though -- systematically devaluing the potential for productive political talk is a form of free speech restriction -- it's a ddos attack against rational discourse - which has the effect of reducing the value of political discourse in general.