The billionaire businessman was forced to halt his motorcade and go through a back entrance to a hotel to give a speech to the California Republican convention and avoid several hundred loud protestors gathered outside.
“That was not the easiest entrance I’ve ever made,” Trump told the gathering in Burlingame, south of San Francisco, after weaving around a barrier and clambering across a road to get to the venue. “It felt like I was crossing the border actually.”
Demonstrators, some of whom held Mexican national flags, at one point rushed security gates at the hotel and police officers had their batons out.
The mogul had already drawn protests in California, with chaotic scenes on Thursday outside a Trump rally in Costa Mesa. Anti-Trump protesters smashed the window of a police patrol car and blocked traffic and some 20 people were arrested.
Protests have become common outside rallies for Trump who has earned ardent critics, as well as support from Republican voters, for his rhetoric against illegal immigration. His campaign abandoned a rally in Chicago last month after clashes between his supporters and protesters.
He has accused Mexico of sending drug dealers and rapists across the U.S. border and has promised to build a wall and make Mexico pay for it.
Trump, who described himself this week as the party’s presumptive nominee, would take a large stride toward knocking his Republican rivals out of the presidential race if he wins the Indiana primary next week.
On Friday, he said he is approaching the 1,237 delegates needed to clinch the nomination. Trump, who has run as a political outsider and only recently started making inroads to the Republican establishment, called for the party to band together behind him. But said he could win the White House without them if needed.
“There should be and there has to be unity. Now with that being said, would I win, can I win without it? I think so, to be honest,” Trump told the convention. His speech drew applause, though not the fervent reception of his usual campaign rallies.