the Carabinieri car is surrounded by "Demonstrators", Carlo seems to throw the extinguisher against the car in the next moment. Directly in front of the car you can see a man with a red tshirt, quite calm, looking what's happening   

he is picking up cobblestones just after the shootings...
  

and then he's running away .... rather walking than running comparing to the other demonstrant who's really running for his life (another photo of the 2^nd man)