SAN DIEGO, May 28 (UPI) -- San Diego police arrested at least 35 protesters outside a rally for presumptive Republican presidential nominee Donald Trump on Friday.
As Trump spoke inside the San Diego Convention Center, more than 1,000 protesters demonstrated outside the venue.
The demonstrations started peacefully. But the situation escalated when people left the arena around 4:30 p.m.
San Diego police in riot gear gathered throughout the Gaslamp Quarter of downtown.
Some protesters started throwing things. Then police began to disperse the crowd as they declared the protests unlawful.
Police pepper-sprayed several protesters.
No property was damaged and there were no injuries, according to San Diego police.
Some protesters held Mexican flags and flags from other countries and yelled, "Dump Donald Trump."
Trump supporters chanted, "You can't vote," and, "Build that wall!"
San Diego Police Chief Shelley Zimmerman said before the rally police would not allow violence or unlawful behavior.
"The safety of our public is paramount," Zimmerman said. "The whole goal is to provide a sale environment for everyone."
Late in the evening, the GasLamp Quarter was cleared and several hundred people were moved onto Harbor Drive. Police also used helicopters to disperse the crowd.
Trump asked security to remove protesters.
"Thank you, you have a beautiful voice," Trump replied to a protester who shouted obscenities his way. "Get 'em out."
Trump also earlier spoke in Fresno, Calif., ahead of the state's June 7 primary.
Fewer demonstrators were on hand in Fresno.
He spoke about the water situation, declaring "there is no drought" although the state had one of its driest years in 2015
"If I win, believe me, we're going to start opening up the water so that you can have your farmers survive, so that your job market will get better," Trump told a few thousand cheering supporters at Selland Arena.