Protesters Destroy Police Cars, Wave Mexican Flags At Trump's First Rally in California

Republican presidential frontrunner Donald Trump is widely expected to win the California primary on June 7, the last contest of the 2016 primary campaign. He leads by roughly 20 points, according to recent polling, and began his campaign there on Thursday night.

But that reality doesn't mean that the race there will be easy for him, in a state that is nearly 40 percent Hispanic and where just 28 percent of registered voters identify themselves as Republicans.

Chaos broke out outside of Trump's first campaign rally in the state on Thursday night. Officers with the Orange County Sheriff's Department on horse back and in riot gear attempted to quell the protests, as demonstrators smashed the window of a police squad car, marched in protest and blocked traffic, some carrying Mexican flags and homemade signs comparing Trump to Hitler.

Some 20 demonstrators were ultimately arrested on Thursday outside Trump's campaign rally at the county fair grounds in Costa Mesa, California, the sheriff's department said on its Twitter account.

Meanwhile, inside the southern California event, the Republican presidential front-runner vowed to his supporters to get tough on illegal immigration if elected. Trump was joined on stage by members of the Remembrance Project, an anti-immigration group that represents the families of those killed by illegal immigrants, according to RealClearPolitics.

"They all have a very similar story to tell," Trump said, according to the news site. "People that shouldn't have been here, people that should have never been allowed to come over the border and they come here like its nothing, they walk through it like its nothing. … We're going to stop it and we're going to build a wall."

Trump rallied supporters Thursday night in Costa Mesa, a city of more than 100,000 people, a third of whom are Hispanic or Latino, hoping to garner support in California where voters will go to the polls during the state's Republican primary on June 7.

A strong primary win in California for the billionaire could thrust him above the delegate count needed to secure the Republican nomination for president and avoid a contested party convention in July.

During the campaign stop on Thursday, Trump suggested that building a wall on the border between Mexico and the United States, a popular theme of his presidential campaign, would stop drugs from coming into this country.

"The drugs are poisoning our youth and a lot of other people and we are going to get it stopped," he said, telling the crowd that he would force Mexico to pay for the wall.

After the event, local news showed hundreds of demonstrators surrounding vehicles, waving Mexican flags and holding signs in protest of Trump outside of the Orange County Fair and Event Center. At least one demonstrator was shown jumping on the top of a police car while other demonstrators were seen shaking a police vehicle.

People jumping on police car outside — Jeremy Diamond (@JDiamond1)April 29, 2016

Some Trump supporters clashed with protesters on Thursday night, but the Orange County Sheriff's office said that no major injuries were reported.

Trump has come under fire from rivals for fueling unrest with his rhetoric as several of his rallies around the country have been met by protests during the last several months.

A — Jeremy Diamond (@JDiamond1)April 29, 2016

The California rally was hardly the first time that violence has broken out at a Trump event, though it has been several weeks since the campaign has seen serious protests.

Trump thanked supporters for the huge crowds that showed up to see him on Thursday night in a tweet, but made no mention of the protests.

Thank you Costa Mesa, California! 31,000 people tonight with thousands turned away. I will be back! — Donald J. Trump (@realDonaldTrump)April 29, 2016

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