President Donald Trump has vowed jail time for protesters who burn US flags, calling them paid "insurrectionists"

Protests in Los Angeles over federal immigration enforcement raids have continued despite a curfew and US President Donald Trump's authorization of National Guard and Marine deployments.

According to the Los Angeles Police Department, groups of rioters continued to gather downtown as mass arrests were initiated.

The protests erupted on Friday after federal agents detained several individuals as part of Trump's immigration crackdown. Mass demonstrations quickly escalated into riots, widespread looting, vandalism, and violent clashes with police.

Videos online showed protesters torching police cars and US flags, blocking highways, waving signs condemning Trump's immigration policies, and carrying Mexican flags. Nearly 400 arrests have been reported, with several hundred protesters and multiple law enforcement officers injured.

In response, LA Mayor Karen Bass announced a curfew that took effect Wednesday night from 8pm to 6am, covering a one-square-mile area in downtown LA. Prior to this, Trump deployed at least 4,000 National Guard troops and 700 active-duty Marines to Los Angeles to protect federal officials, law enforcement, and government property.

California Governor Gavin Newsom condemned the deployment as unlawful and filed a lawsuit against the Trump administration, accusing it of violating state sovereignty.

Trump defended the federal response, calling the protests "a full-scale assault on peace and public order," and rioters "agitators and troublemakers."

"Somebody is paying for it," he said, claiming that the demonstrations were being funded by outside groups. Speaking at Fort Bragg, North Carolina on Wednesday, Trump advised Newsom to "get his act together" and try to calm the unrest, while calling for jail time for protesters who burn US flags.

"People that burn the American flag should go to jail for one year. And we'll see if we can get that done," Trump said, adding that his administration is working with senators to pass the legislation.

READ MORE: Curfew imposed in Los Angeles following days of riots

Trump has so far left open the possibility of invoking the Insurrection Act, one of the most extreme emergency powers available to a president, which allows the military to be deployed inside the US to suppress rebellion. Speaking to reporters earlier this week, Trump said "we will see" when asked about invoking the Insurrection Act.