Behind this police car is a massive group of marching Spanish protesters that I followed for blocks from my hotel in the Passeig de Gracia district to the Gothic Quarter. http://www.france24.com/en/20120912-catalonian-separatists-stage-mass-protest-barcelona-autonomy-madrd-crisis-spain
Large demonstrations have been a fairly common scene since I've first arrived in the City.
What can't be seen in this photo is the sound of the firing of Police rubber bullets.