LOS ANGELES — Around 300 National Guard troops arrived in Los Angeles early Sunday on orders from President Donald Trump, staging outside a federal complex that remained largely quiet and without major protests after two days of clashes with immigration authorities.

The deployment marked the first time in six decades that a state’s national guard was activated without a request from its governor, according to the Brennan Center for Justice.

On Sunday morning, some of the troops were stationed outside the Metropolitan Detention Center in downtown Los Angeles, dressed in tactical gear and holding long guns in front of armored vehicles.

A small number of protesters gathered at the scene, along with Rep. Maxine Waters, a Democrat, who demanded entry to the facility.

The arrival of the National Guard followed two days of protests that began Friday in downtown Los Angeles, then spread Saturday to Paramount, a heavily Latino city south of Los Angeles, and neighboring Compton.

As federal agents set up a staging area Saturday near a Home Depot in Paramount, demonstrators sought to block Border Patrol vehicles, with some people hurling rocks and chunks of concrete.

In response, agents in riot gear unleashed tear gas, flash-bang explosives and pepper balls.

Tensions were high after a series of sweeps by immigration authorities the previous day, as the weeklong tally of immigrant arrests in the city climbed past 100. A prominent union leader was arrested while protesting and accused of impeding law enforcement.

The deployment of the National Guard came over the objections of Gov. Gavin Newsom, who accused Trump of a “complete overreaction” designed to create a spectacle of force.

In a directive Saturday, Trump invoked a legal provision allowing him to deploy federal service members when there is “a rebellion or danger of a rebellion against the authority of the Government of the United States.”

Newsom called Trump on Friday night and they spoke for about 40 minutes, according to the governor’s office. It was not clear if they spoke Saturday or Sunday.

There was some confusion surrounding the exact timing of the guard’s arrival. Shortly before midnight local time Saturday, Trump congratulated the National Guard on a “job well done.” But less than an hour later, Mayor Karen Bass said troops had yet to arrive in the city.

Homeland Security Secretary Kristi Noem said Sunday that the purpose of the deployment was to “provide security for operations and to make sure that there are peaceful protests.”

The troops included members of the 79th Infantry Brigade Combat Team, according to a social media post from the Department of Defense.

In a signal of the administration’s aggressive approach, Defense Secretary Pete Hegseth also threatened to deploy active-duty Marines “if violence continues” in the region.

Vermont Sen. Bernie Sanders said the order by Trump reflected “a president moving this country rapidly into authoritarianism” and “usurping the powers of the United States Congress.”

House Speaker Mike Johnson, a staunch Trump ally, endorsed the president’s move, doubling down on Republicans’ criticisms of California Democrats.

“Gavin Newsom has shown an inability or an unwillingness to do what is necessary, so the president stepped in,” he said.

Trump’s order made rare use of federal powers to bypass the authority of Newsom, a Democrat, who called the deployment “purposefully inflammatory.”

One expert said it was the first time since 1965 that a president had activated a state’s National Guard force for a domestic operation without a state governor’s express approval. That year, President Lyndon B. Johnson sent troops to Alabama to protect Civil Rights demonstrators.

Newsom’s office said National Guard troops had been deployed to three locations in the city, the first of what Trump said would be at least 2,000 Guard members to be activated in response to the demonstrations.

“For the federal government to take over the California National Guard, without the request of the governor, to put down protests is truly chilling,” said Erwin Chemerinsky, the dean of the law school at the University of California, Berkeley. “It is using the military domestically to stop dissent.”

The National Guard was last federalized in 1992, Goitein said, when President George H.W. Bush sent troops to Los Angeles to control riots after police officers were acquitted in the beating of Rodney King. That deployment was requested by the California’s governor at the time, Pete Wilson.

Trump and his aides have often lamented that not enough was done by Minnesota’s governor to quell protests after the death of George Floyd in 2020.

Also in 2020, in the final days of Trump’s first presidential term, military helicopters were used to rout peaceful protesters demonstrating against police violence near the White House.

During a campaign rally in 2023, Trump made clear that he was not going to hold back in a second term: “You’re supposed to not be involved in that, you just have to be asked by the governor or the mayor to come in — the next time, I’m not waiting.”

The New York Times contributed.