From Victoria Spilabotte:
A protest outside a Trump rally in Costa Mesa quickly escalated to violence and destruction after angry protestors smashed the back windshield of a patrol car and then tried to flip it.
In total five police cruisers were damaged.
"When you start damaging people's property whether or not it's a ppolice vehicle or an individuals property obviously that's a violation of law," Lt. Marc Stichter, Orange County Sheriff, said.
Police arrested 17 people after the rally Thursday night.
Officers moved in on horseback wearing riot gear to break up the crowds.
Ryan Clap, who lives just around the corner from the fair grounds, watched in disbelief.
"What I was worried about is the safety of my family and my neighborhood," Clap said. "I actually met a lot of neighbors last night just seeing what was going on."
At one point anti-Trump protestors clashed with supporters.
Paramedics treated a man after his face was bloodied.
Alec Gerein, who attended the rally wearing his hat reading "Make America Great Again," was wary about walking home.
"For the most part it seemed pretty peaceful, but then a little later people started to create problems," Gerein said. "There was tear gas and some people got into fights."
Trump spoke to a sold-out crowd of more than 8-thousand people.
Police estimate that 2-thousand more were turned away from the rally.
Protestors on the streets held up signs reading "Dump Trump."
Others graffitied walls with death threats to Trump.
Crews said it took three hours to clean up the vandalism.
Republican presidential front-runner Donald J. Trump is scheduled Friday to speak at a luncheon at the California Republican Party Convention in Burlingame, one day after a rally in Costa Mesa resulted in the arrests of more than 20 protesters.
Trump began his speech to a capacity crowd of around 8,000 at the Pacific Amphitheatre at the Orange County Fair & Event Center Thursday night by calling to the stage relatives of people who had been killed by immigrants without legal permission to be in the country.
Jamiel Shaw, whose high school football standout son -- Jamiel Shaw II -- was killed in 2008 by a gang member in the country without legal permission, told the crowd when he saw television coverage of Trump announcing his candidacy on June 16, 2015, "for the first time, it gave me real hope."
Trump stuck to his usual themes, including criticizing his opponents for the Republican nomination, Texas Sen. Ted Cruz and Ohio Gov. John Kasich, and the Democratic front-runner, former Secretary of State Hillary Clinton.
He also called for laws to permit waterboarding of terrorism suspects; removing restrictions on the armed forces; closing the borders; bringing jobs back to the U.S.; and protecting the Second Amendment.
Following the speech, hundreds of protesters raged outside the Orange County Fair & Event Center in Costa Mesa banging on cars, throwing rocks at motorists and attacking police.
Hundreds of demonstrators, most believed to be anti-Trump protesters, thronged the intersection of Fair Drive and Fairview Drive, outside the Orange County Fair & Event Center by 8:30 p.m. Some of those in the crowd were thought to be Trump supporters who were unable to get inside to see the candidate's speech.
People had been gathering at the fairgrounds since about 4 p.m. Eventually, the crowd stopped traffic around the venue as protesters marched in the streets carrying U.S and Mexican flags, according to the Los Angeles Times.
"Dump the Trump" signs sprouted through the crowd as demonstrators smashed a window on a police cruiser and punctured the tires on a police SUV. Some protesters tried to overturn a police car as well, according to The Times.
Colby Nicholson, a 30-year-old Trump supporter told The Times, "These people are stupid, but Americans are stupid in general. These are all underage Mexican high schoolers who have nothing to do."
Juan Carlos, 16, told The Times his family came from Mexico to the U.S. and he was here to support the protesters and others like him.
"Donald Trump is worthless," Carlos told The Times. "There won't be a United States without Mexicans."
Costa Mesa police and about 50 Orange County sheriff's deputies, including mounted units, worked to clear the intersection and get the crowd to disperse, according to Orange County sheriff's Lt. Mark Stichter.
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