The California governor, Gavin Newsom, called the potential deployment of US marines in his state “deranged” after the secretary of defense threatened the use of such troops amid a promise to deploy the national guard after an immigration crackdown saw police use teargas on protesters.

“The Secretary of Defense is now threatening to deploy active-duty Marines on American soil against its own citizens. This is deranged behavior,” Newsom wrote on X.

Earlier Pete Hegseth, Donald Trump’s controversial and hardline defense secretary, had raised the possibility of deploying US marines onto the streets of the Democrat-run state amid the protests that had erupted in the wake of Ice raids in the state.

“Under President Trump, violence & destruction against federal agents & federal facilities will NOT be tolerated. It’s COMMON SENSE,” Hegseth wrote on X, the social media platform formerly known as Twitter.

“If violence continues, active duty Marines at Camp Pendleton will also be mobilized – they are on high alert,” Hegseth said. Camp Pendleton is a large military base south of Los Angeles and north of San Diego.

Tensions in Los Angles had begun on Friday, when protesters clashed with law enforcement officials conducting immigration raids on multiple locations in the sprawling city’s downtown.

On Saturday, US immigration authorities extended enforcement action into Paramount, a majority Latino area south-east of Los Angeles, and were met with more protests outside an industrial park.

A stand-off developed between border patrol personnel in riot gear and gas masks and protesters. As demonstrations continued law enforcement deployed teargas and protesters also threw objects at them. At least one car was set alight.

Trump then promised to send in the national guard – a move that many critics have feared might happen during his second administration amid fears that the US is sliding into authoritarianism.

Though troops have not yet appeared on the streets of Los Angeles, Newsom confirmed the move, saying on X that the federal government was “moving to take over” the state’s national guard. The governed add that the mobilization was “purposefully inflammatory” and would “escalate tensions”.

“The federal government is taking over the California National Guard and deploying 2,000 soldiers in Los Angeles – not because there is a shortage of law enforcement, but because they want a spectacle,” Newsom said later. “Don’t give them one.”

The Los Angeles mayor, Karen Bass, said on X that no national guard had yet been deployed. “Just to be clear, the National Guard has not been deployed in the City of Los Angeles,” Bass said on X.

Bill Essayli, the US attorney for the central district of California, said late Saturday the national guard was expected to arrive in roughly the next 24 hours. He told local TV station told KCBS/KCAL that demonstrators had the right to protest peacefully, but those who were would be subject to federal prosecution.

“We will identify you, we will come find you, and we will get you,” he warned.

On his own social media platform, Truth Social, Trump praised the national guard, despite no evidence they had yet been put on the streets. “Great job by the National Guard in Los Angeles after two days of violence, clashes and unrest,” he said in a post filled with insults at Bass and Newsom.

“These Radical Left protests, by instigators and often paid troublemakers, will NOT BE TOLERATED. Also, from now on, MASKS WILL NOT BE ALLOWED to be worn at protests. What do these people have to hide, and why???” he added.

Trump has long promised mass immigration raids across the US after campaigning in part last year on anti-immigrant sentiment. Since he returned to office Ice raids have increased, in particular targeting some areas traditionally left alone such as court houses where immigrants might be attending hearings.

During afternoon protests at a downtown federal detention facility on Friday, David Huerta, the president of the California branch of the Service Employees International Union, was arrested.

Huerta, who was injured and detained, released a statement to the Los Angeles Times from the hospital, saying: “Hard-working people, and members of our family and our community, are being treated like criminals. We all collectively have to object to this madness because this is not justice,” he added.