The riot began with a police shooting...
Some "police" were shooting protesters in Egypt... remember the Egypt riots not too long ago? Remember how that worked out for the "police"?
Aggressive violence can lead to more backlash in a civil unrest situation.
looters /= rioters.
A rioter may be violent, while a looter by definition is stealing things and causing harm, generally during a time of upheaval or turmoil. A belligerent protester should be treated differently (by police and the general public) than someone who is setting buildings on fire and breaking into houses/businesses and stealing.