US Northern Command (USNORTHCOM) has said that it will send 700 Marines to Los Angeles, California, to help respond to immigration protests.

"The activation of the Marines is intended to provide Task Force 51 with adequate numbers of forces to provide continuous coverage of the area in support of the lead federal agency," USNORTHCOM said in a statement on Monday.

Task Force 51 is comprised of approximately 2,100 National Guard soldiers in a Title 10 status and 700 active-duty Marines, it said, adding that Task Force 51 forces have been trained in de-escalation, crowd control and standing rules for the use of force.

The US Secretary of Defense and USNORTHCOM earlier announced that 500 Marines would be mobilised to respond, but the increased number of servicemen being sent marks a significant escalation in Trump's use of the military to combat protesters.

So far, 300 members of the California Army National Guard's 79th Infantry Brigade Combat Team have arrived in Los Angeles, and the troops could remain there for up to 60 days.

The deployment of the National Guard and the mobilisation of the Marines by Trump has drawn ire from California Governor Gavin Newsom and Los Angeles Mayor Karen Bass. Both have said that local law enforcement can handle the protests and that Trump's deployment of federal troops is being used as a political ploy to make the situation more volatile.

Newsom on Monday announced a lawsuit against Trump, saying that the president's deployment of the National Guard was illegal and violated state sovereignty.

"We are suing Donald Trump. This is a manufactured crisis," Newsom wrote on X. "He is creating fear and terror to take over a state militia and violate the US constitution."

Trump has dismissed those claims, saying that his executive actions were helping take care of the crisis, which he said was getting out of hand.

"I think we have it very well under control," he said in a statement. "I think it would have been a very bad situation. It was heading in the wrong direction. It's now headed in the right direction."

"And we hope to have the support of Gavin, because Gavin is the big beneficiary as we straighten out his problems," he continued. "I mean, his state is a mess."

The protests began last Friday after Immigration and Customs Enforcement (ICE) agents raided local businesses and detained hundreds of people suspected of living in the US illegally.

The Trump administration said the ICE raids will continue as part of the president's plan to crack down on illegal immigration.