LATimes:

Hundreds of demonstrators filled the street outside the Orange County amphitheater where Donald Trump held a rally Thursday night, stomping on cars, hurling rocks at motorists and forcefully declaring their opposition to the Republican presidential candidate. Traffic came to a halt as a boisterous crowd walked in the roadway, some waving American and Mexican flags. Protesters smashed a window on at least one police cruiser, punctured the tires of a police sport utility vehicle, and at one point tried to flip a police car. One Costa Mesa police officer was struck in the head by a rock thrown by a protestor, authorities said. The officer wasn't injured because he was protected from by his riot helmet.

Some are saying riots help Trump.