Hundreds of people marched through Los Angeles on Sunday in May Day rallies that took aim at Republican presidential front-runner Donald Trump for his anti-illegal immigration platform that includes building a wall along the U.S. border with Mexico.

The rallies in America's second most populous city, which has a large immigrant population, came days after protesters smashed the window of a police car and blocked traffic outside a Trump campaign event in Costa Mesa, California, 40 miles southeast of Los Angeles.

On Friday, demonstrators blocked the entrance of a hotel hosting the California Republican convention in Burlingame, south of San Francisco, forcing Trump to halt his motorcade and go through a back entrance to deliver his speech.

Protests have become common outside rallies for Trump, 69, the New York billionaire businessman. He has aroused criticism for his pledge to deport all the country's illegal immigrants, even as it helped propel him in the race for the Republican nomination for the Nov. 8 election to succeed Democratic President Barack Obama.

He has accused Mexico of sending drug dealers and rapists across the U.S. border and has promised to build a wall along the southern border and make Mexico pay for it.

Three separate marches were planned in Los Angeles on Sunday and began peacefully around noon, with several hundred people championing a variety of causes, including immigrant and worker rights.

Members of the boisterous crowd carried a large blow-up effigy of Trump holding a Ku Klux Klan hood, along with signs that read: "Dump Trump."

Others waved Mexican or U.S. flags or signs that called for immigration reform and an end to deportations.

A Los Angeles Police Department spokeswoman said no arrests had been made as of midafternoon, and there were no reports of violence. She declined to give an estimate of the crowd size.

Trump said on Sunday he will have essentially sealed the Republican nomination if he wins Tuesday's contest in Indiana, where he holds a big lead over chief rival Ted Cruz, a U.S. senator from Texas.

California holds its presidential primary on June 7.