(CNN) — President Donald Trump has signed a presidential memorandum deploying 2,000 National Guardsmen to disperse protests over immigration activity in the Los Angeles area, the White House said in a statement Saturday night.

“The Trump Administration has a zero tolerance policy for criminal behavior and violence, especially when that violence is aimed at law enforcement officers trying to do their jobs,” White House press secretary Karoline Leavitt said in a statement. “These criminals will be arrested and swiftly brought to justice.”

On Saturday, protesters gathered in Paramount, California. Assemblymember José Luis Solache said four people were arrested. Tear gas and flash bangs have been used on the second consecutive day of immigration demonstrations.

The FBI is investigating alleged instances of demonstrators obstructing immigration enforcement operations in Los Angeles Friday and Saturday, the bureau’s deputy director, Dan Bongino, said on social media Saturday.

Trump called in the National Guard to “address the lawlessness that has been allowed to fester,” the White House said.

“In recent days, violent mobs have attacked ICE Officers and Federal Law Enforcement Agents carrying out basic deportation operations in Los Angeles, California,” the statement said. “These operations are essential to halting and reversing the invasion of illegal criminals into the United States. In the wake of this violence, California’s feckless Democrat leaders have completely abdicated their responsibility to protect their citizens.”

Earlier on Saturday, Trump’s border czar, Tom Homan, said in an interview with Fox News that the National Guard would be called in to respond to the protests.

“We’re making Los Angeles safer, and Mayor (Karen) Bass ought to be thanking us for making her city safer,” Homan said. “This is about enforcing the law, and again, we’re not going to apologize for doing it.”

Stephen Miller, the White House deputy chief of staff, said the government has two choices: “Deport the invaders, or surrender to insurrection.”

The Department of Justice also criticized California officials as protests over federal immigration enforcement operations entered a second day Saturday.

“The violent targeting of law enforcement in Los Angeles by lawless rioters is despicable and Mayor Bass and Governor Newsom must call for it to end. The men and women of ICE put their lives on the line to protect and defend the lives of American citizens,” said Assistant Secretary Tricia McLaughlin in a Saturday statement.

Department of Homeland Security Secretary Kristi Noem posted a “message to the LA rioters” on social media Saturday. “You will not stop us or slow us down,” she wrote. “@ICEgov will continue to enforce the law. And if you lay a hand on a law enforcement officer, you will be prosecuted to the fullest extent of the law.”

The Los Angeles County Sheriff’s Department said it was not involved in immigration enforcement and was working to ensure the safety of the public.

“The Sheriff’s Department was not involved in any federal law enforcement operations or actions and responded solely for traffic and crowd control management,” the LASD said in a statement.

The response to the protests drew a conflict between ICE and the Los Angeles Police Department. “Our brave officers were vastly outnumbered, as over 1,000 rioters surrounded and attacked a federal building,” said ICE in a statement. “It took over two hours for the Los Angeles Police Department to respond, despite being called multiple times.”

But the LAPD said that, “Contrary to the claim that LAPD delayed its response for over two hours, our personnel mobilized and acted as swiftly as conditions safely allowed.”

Protests started Friday

The protests started Friday afternoon. Police on Friday night issued a citywide tactical alert nearly two hours after declaring protests across the downtown area unlawful assemblies. “The use of less lethal munitions has been authorized by the Incident Commander,” LAPD’s Central Division wrote in a post on X.

Videos of the scene show law enforcement officers in riot gear, wielding batons, holding shields and throwing smoke bombs into the crowd. Protesters chanted “Free them all” and held signs with messages including “Full Rights for All Immigrants” and “Stop the Deportations.” Video shows several officers in riot gear pinning at least one person to the ground.

The protest came after at least 44 people were arrested by federal immigration agents earlier in the day, The Associated Press reported, after Immigration and Customs Enforcement officers executed search warrants at three locations, according to a spokesperson for Homeland Security Investigations. The arrests come amid Trump’s crackdown on immigration, which has involved waves of raids and deportations across the country.

Bass, the Los Angeles mayor, characterized the immigration arrests as “mass chaos,” according to CNN affiliate KABC. The mayor said she hadn’t been told about the raids in advance. “It sows a sense of terror throughout the community,” she said. “ICE was literally chasing people down the street.”

The federal law enforcement activity came on the same day multiple sources told CNN the Trump administration is preparing for “large-scale” cancellation of federal funds for California.

CNN has reached out to DHS for further information.

One of the Friday raids was in the city’s Fashion District, where agents served a search warrant after a judge determined a business was allegedly using fictitious documents for some of its workers, US Attorney’s office spokesperson Ciaran McEvoy told CNN.

Union leader arrested

David Huerta, the president of the Service Employees International Union California, was arrested by federal agents after allegedly attempting to obstruct their access at a worksite, US Attorney for the Central District of California Bill Essayli said in a post on X.

“Let me be clear: I don’t care who you are—if you impede federal agents, you will be arrested and prosecuted,” Essayli said.

After being treated for injuries from his arrest, Huerta released a statement condemning the citywide raids.

“Hard-working people, and members of our family and our community, are being treated like criminals,” he said. “We all collectively have to object to this madness because this is not justice. This is injustice. And we all have to stand on the right side of justice.”

“No one should ever be harmed for witnessing government action,” California Gov. Gavin Newsom said in a statement responding to Huerta’s arrest, describing the union president as a “respected leader, a patriot and an advocate for working people.”

Bass said Friday’s immigration arrests were different from previous, more organized actions.

“I’ve been really worried about this from the beginning, and as far as I know, this is the first time this has happened in our city like this,” she told KABC. “We know ICE has been here, but it’s been for targeted arrests; this was just mass chaos.”

“It sows a sense of chaos in our city, and a sense of terror, and it’s just unacceptable.”

The American Civil Liberties Union called on “elected officials to uphold their commitment to all Angelenos — immigrants and non-immigrants alike — by taking all action necessary to grind this oppressive and vile paramilitary operation to a halt and keep our city safe and whole” in a Friday statement.

Protesters face off with police

Protesters gathered outside the Federal Building in downtown Los Angeles at roughly 4 p.m., CNN affiliate KABC reported. At one point, hundreds of activists began marching toward a detention facility on Temple Street.

One video obtained by CNN shows protesters retreating from the building’s entrance after coming face-to-face with the police guarding it. Several projectiles are thrown at officers equipped with body armor and protective shields.

Other videos show the detention center sprayed with anti-ICE graffiti, with some protesters blocking LAPD vehicles close by.

Families and friends who had loved ones taken by immigration authorities visited the detention center to learn more about their status, KABC reported.

A young woman who spoke with the outlet said she went to the building in tears after her father was taken by federal agents.

The LAPD declared an unlawful assembly around 7 p.m. and warned demonstrators were subject to arrest if they remained in the area.

Aerial footage from KABC shows law enforcement throwing smoke bombs on a street to disperse people so they could make way for SUVs and military-style vehicles.

“While the LAPD will continue to have a visible presence in all our communities to ensure public safety, we will not assist or participate in any sort of mass deportations, nor will the LAPD try to determine an individual’s immigration status,” Police Chief Jim McDonnell said in a statement about the immigration enforcement activities.

“I want everyone, including our immigrant community, to feel safe calling the police in their time of need and know that the LAPD will be there for you without regard to one’s immigration status.”

Newsom said in a Saturday statement, “Continued chaotic federal sweeps, across California, to meet an arbitrary arrest quota are as reckless as they are cruel.”

“Donald Trump’s chaos is eroding trust, tearing families apart, and undermining the workers and industries that power America’s economy,” the governor said.