Days after President Donald Trump deployed 2,000 National Guard troops in California to respond to immigration enforcement protests, U.S. Sen. Ed Markey said he would oppose any similar tactics in Massachusetts, which has already come under fire for its “sanctuary” policies.

“If Trump sought to nationalize the National Guard here in Massachusetts, or to send in the Marines, I would fight Trump every single step of the way because it would be one further step toward an authoritarian dictatorship in our country,” Markey told reporters Monday after speaking at a New England Council breakfast.

While California Gov. Gavin Newsom objected, Trump sent in the National Guard as protests escalated around Los Angeles amid federal immigration raids. The president had threatened on social media that the federal government would intervene if Newsom and Los Angeles Mayor Karen Bass “can’t do their jobs” and get the clashes under control.

“What Trump is trying to do in California is wrong. It is authoritarianism on steroids,” Markey said. “We have to, here in Massachusetts, make sure that he understands that we are not going to tolerate having the authority of Gov. Healey or Mayor Wu, or any of our local officials, undermined by his authoritarian techniques to nationalize the National Guard or any other national military body.”

The White House said in a statement Monday that Trump was “stepping up where Democrats won’t” and that California leaders “should be thanking President Trump for stepping up and leading where they refused — and for ridding their streets of criminal illegal immigrant killers, rapists and gangbangers.”

Labor unions and advocates held an “emergency solidarity rally” outside Boston City Hall on Monday to call for the release of David Huerta, the president of SEIU California who was arrested during a protest in Los Angeles.

“It’s important to speak the truth, and I support the calls to make sure that we are calling out when unconstitutional behavior is happening,” Boston Mayor Michelle Wu said when asked whether the event could bring “unwanted attention” to the city.

Trump’s border czar has threatened he’d bring “hell” to Boston, and he visited Massachusetts in March as federal agents arrested 370 people.

Democratic governors, including Gov. Maura Healey, issued a statement Sunday calling Trump’s National Guard deployment an “alarming abuse of power.”

“It’s important we respect the executive authority of our country’s governors to manage their National Guards — and we stand with Gov. Newsom, who has made it clear that violence is unacceptable and that local authorities should be able to do their jobs without the chaos of this federal interference and intimidation,” the statement reads.

Sam Drysdale contributed reporting.