COSTA MESA, Calif. — Raucous crowds of protesters took to the streets in California as Donald Trump brought his Republican presidential campaign to conservative Orange County after sweeping the Northeast GOP primaries.

Dozens of protesters were mostly peaceful Thursday as Trump gave his speech inside the Pacific Amphitheater. After the event, however, the demonstration grew rowdy late in the evening and spilled into the streets.

At least four people were arrested and one Trump supporter had his face bloodied in a scuffle as he tried to drive out of the arena. One man jumped on a police car, leaving its front and rear windows smashed and the top dented in and other protestors sprayed graffiti on a police car and the venue’s marquee.

Dozens of cars — including those of Trump supporters trying to leave — were stuck in the street as several hundred demonstrators blocked the road, waved Mexican flags and posed for selfies.

Police in riot gear and on horseback pushed the crowd back and away from the venue. There were no major injuries and police did not use any force.The crowd began dispersing about three hours after the speech ended.