LAGUNA BEACH – About 500 people rallied along Main Beach on Saturday to demand that President Trump release his tax returns.

Protesters lined two blocks of Pacific Coast Highway, holding homemade signs and chanting “Lock him up!” and “Dump Trump!”

More than 75 drivers honked in support, with one slowing down to raise an “Impeach” sign from his sunroof. A few other drivers shouted their support for Trump.

“Donald Trump works for us,” Cottie Petrie-Norris, a Laguna Beach Democratic Club board member and one of the demonstration’s organizers, said on Friday. “He’s accountable to us.”

The Laguna Beach Democratic Club and an informal women’s group co-hosted Orange County’s sole protest, joining movements in Long Beach, Los Angeles and Riverside. The demonstrators called on Trump to follow presidents who have made their tax returns public for the past 40 years.

“A lot of people are upset,” said Ginger Osborne, who led the women’s group. “Trump said people don’t care. This crowd shows that we do.”

More than 100 other demonstrations calling on Trump to release his tax returns were planned across the country on the nation’s historic tax filing deadline of April 15.

In Washington, D.C., one of Trump’s sharpest critics in the House spoke to protesters at the U.S. Capitol just before they set off on a march to the National Mall. U.S. Rep. Maxine Waters, D-Los Angeles, said there’s nothing to prevent Trump from releasing his income taxes and that “the simple truth is he’s got a lot to hide.”

“If he thinks he can get away with playing king, he’s got another thought coming,” Waters said.

At least four people were arrested Saturday in Berkeley after clashes between Trump opponents and supporters holding unrelated rallies in a downtown park. After Trump supporters said they would hold a “Patriot Day” rally, counter-protesters decided to hold a rally at the same place.

Actress and producer Justine Bateman, who addressed several thousand people at a rally in downtown Los Angeles, said Americans need “financial statement proof” that Trump is not beholden to any business interests or country other than the U.S.

U.S. Rep. Lou Correa, D-Santa Ana, has supported a bill to require Trump and future presidential candidates to make their returns public.

“As elected officials, you want to be transparent with your voters,” Correa said Friday. “In my opinion, the more transparency the better. That’s one of the functions of democracy.”

Trump has said he would not release his tax returns because they are under audit, and his senior adviser Kellyanne Conway has said the public isn’t interested in seeing them. Some Republicans say Trump should focus more on international conflicts and healthcare than his taxes.

Stephen Masek, a Mission Viejo environmental consultant, accused Democrats of trying to make the tax returns “a big issue.”

“There’s no reason on earth for President Trump to release his tax returns,” Masek said in an interview Friday. “The election is over. It shows an extraordinary level of desperation that they’re talking about tax return releases this far after the election.”

By 1 p.m. Saturday, about 500 protesters turned out for the demonstration at Main Beach, according to a police estimate.

Among them was Nick Walker, a retired businessman from San Clemente, who had attended the women’s march in Santa Ana in January.

Walker said he was inspired to come to Laguna Beach after seeing the crowds in Santa Ana.

“We want to make sure everybody has their fair share of taxes,” he said. “We don’t want people to have an advantage because they’re wealthy.”

As the demonstration wound down, two women wearing the red “Make America Great Again” caps that Trump made popular during his campaign argued with a protester about other issues – involving immigration and Melania Trump – for about 30 minutes.

But the protest was mostly peaceful, in contrast to the Make America Great Again rally held on March 25 in Huntington Beach that attracted about 2,000 Trump supporters and a group of about 30 protesters, according to an official estimate.

A violent brawl ensued at that event and several people were assaulted.

The Associated Press contributed to this report.