LOS ANGELES (AP) California Gov. Gavin Newsom said he planned to file a lawsuit Monday against President Donald Trump in response to the administration’s extraordinary deployment of the National Guard to confront immigration protesters who took to the streets in Los Angeles.

“Commandeering a state’s National Guard without consulting the Governor of that state is illegal and immoral,” Newsom, a Democrat, told MSNBC on Sunday.

The streets of the sprawling city of 4 million people were mostly quiet Monday morning, the day after crowds blocked off a major freeway and set self-driving cars on fire as law enforcement responded with tear gas, rubber bullets and flash-bang grenades.

Sunday’s protests were centered in several blocks of downtown and a handful of other places. It was the third and most intense day of demonstrations against Trump’s immigration crackdown in the region, as the arrival of around 300 Guard troops spurred anger and fear among many residents.

Many protesters dispersed as evening fell and police declared an unlawful assembly, a precursor to officers moving in and arresting those who don’t leave. Some of those who stayed threw objects at police from behind a makeshift barrier. Others hurled chunks of concrete, rocks, electric scooters and fireworks at California Highway Patrol officers and their vehicles parked on the closed southbound 101 Freeway. Officers ran under an overpass to take cover at one point.

The Guard was deployed specifically to protect federal buildings, including the downtown detention center where protesters concentrated.

Los Angeles Police Chief Jim McDonnell said officers were “overwhelmed” by the remaining protesters. He said they included regular agitators who show up at demonstrations to cause trouble.

Several dozen people were arrested throughout the weekend. One was detained Sunday for throwing a Molotov cocktail at police and another for ramming a motorcycle into a line of officers.

Trump responded to McDonnell on Truth Social, telling him to arrest protesters in face masks.

“Looking really bad in L.A. BRING IN THE TROOPS!!!” he wrote.

Governor says Guard not needed

Newsom called on Trump to rescind the Guard deployment in a letter Sunday afternoon, calling it a “serious breach of state sovereignty.”

The governor, who was was in Los Angeles meeting with local law enforcement and officials, also told protesters that they were playing into Trump’s plans and would face arrest for violence or property destruction.

“Trump wants chaos and he’s instigated violence,” he said. “Stay peaceful. Stay focused. Don’t give him the excuse he’s looking for.”

The deployment appeared to be the first time in decades that a state’s National Guard was activated without a request from its governor, a significant escalation against those who have sought to hinder the administration’s mass deportation efforts.

McDonnell pushed back against claims by the Trump administration that the LAPD had failed to help federal authorities when protests broke out Friday after a series of immigration raids. He said his department responded as quickly as it could and had not been notified in advance of the raids.

Newsom, meanwhile, has repeatedly said that California authorities had the situation under control. He mocked Trump for posting a congratulatory message to the Guard on social media before troops had even arrived in Los Angeles, and he told MSNBC that Trump never floated deploying the Guard during a Friday phone call. He called Trump a “stone cold liar.”

The admonishments did not deter the administration.

“It’s a bald-faced lie for Newsom to claim there was no problem in Los Angeles before President Trump got involved,” White House spokesperson Abigail Jackson said in a statement.

Clashes escalate as National Guard troops arrive

National Guard troops stood shoulder to shoulder Sunday morning in LA, carrying long guns and riot shields as protesters shouted “shame” and “go home.” After some demonstrators closely approached the Guard members, another set of uniformed officers advanced on the group, shooting smoke-filled canisters into the street.

Minutes later, the Los Angeles Police Department fired rounds of crowd-control munitions to disperse the protesters, who they said were assembled unlawfully. Much of the group then moved to block traffic on the 101 freeway until state patrol officers cleared them.

Nearby, at least four self-driving Waymo cars were set on fire, sending large plumes of black smoke into the sky and exploding intermittently. By evening, police had shut down several blocks of downtown Los Angeles.

Flash-bang grenades echoed out every few seconds into the evening.

Deployment follows days of protest

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

Federal agents arrested immigrants in LA’s fashion district, in a Home Depot parking lot and at several other locations on Friday. The next day, they were staging at a Department of Homeland Security office near another Home Depot in Paramount, which drew out protesters who suspected another raid. Federal authorities later said there was no enforcement activity at that Home Depot.

The weeklong tally of immigrant arrests in the LA area climbed above 100, federal authorities said. Many more were arrested while protesting, including a prominent union leader who was accused of impeding law enforcement.

The last time the National Guard was activated without a governor’s permission was in 1965, when President Lyndon B. Johnson sent troops to protect a civil rights march in Alabama, according to the Brennan Center for Justice.

Trump says there will be ‘very strong law and order’

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.”

He said he had authorized the deployment of 2,000 members of the National Guard.

Trump told reporters Sunday as he prepared to board Air Force One in Morristown, New Jersey, that there were “violent people” in Los Angeles “and they’re not going to get away with it.”

In San Francisco, officers arrested dozens of protesters Sunday night after a group refused to disperse, police said in a statement on social media.

Officers monitoring one protest declared an unlawful assembly when people in the group became violent, the San Francisco Police Department said. Many protesters left the scene, but some remained while others moved to another area where they vandalized buildings and a police vehicle.

___

Offenhartz reported from New York. Associated Press Writer Michelle Price contributed to this report from Bridgewater, New Jersey.