

Believable.
However, officers or hired thugs in plain clothes infiltrating protests and inciting violence in order to give a reasonable excuse for the military/police at shutting them down is a commonly used and widespread tactic. So, was it violent protesters or violent military/government staging an act? Well, the track record stands against official powers.
In favour of your argument I will say that violent individuals will almost always take advantage of a protest to lash out selfishly. It is unavoidable. Yet, a government having a one-sided overwhelming force responding to limited civilian violence with even more overbearing violence, the bias it will face in regards to trust will increase exponentially.
Well, well, well… I sure hope this might mean a sale on the original until this gets released.