Police in Portland, Oregon, U.S., have classified the anti-Trump protests in the area as a “Class C felony” after a once peaceful protest turned into a riot.

A riot is a Class C felony in Oregon.

Demonstrators were seen attacking drivers and committing acts of vandalism during their march against Donald Trump’s election Thursday night.

According to KPTV, one driver had her windshield smashed and someone painted “Capitalism kills” on a nearby convenience store.

The state Department of Transportation briefly shut down Interstate 5 between the Marquan Bridge and the Fremont Bridge due to the demonstration.

Parts of Interstate 84 were also temporarily closed.

Protesters in Portland’s Pearl District were breaking windows of several businesses and some were arming themselves with rocks from a construction site, police said.

“People attending any of the various protest events are encouraged to obey all laws and be respectful of others who are using city streets, freeways and mass transit.

“Marching into and blocking streets is illegal, and dangerous to protesters as well as road users and has a significantly negative impact to our community.

“Pedestrians walking on the freeway is illegal and extremely dangerous to all road users,” Portland police said.

KPTV reported that the groups Don’t Shoot Portland and Black Lives Matter combined in Portland to become Portland’s Resistance.

The founder told the station that “Trump is going to be our president. We need to save our city and hopefully allow people to come here to be a city where there is hope.”

Anti-Trump demonstrations erupted across the U.S. for the second straight night.

The protests took place in Portland, Chicago and New York.

In New York City, a large group of demonstrators once again gathered outside Trump Tower on Fifth Avenue Thursday night chanting angry slogans and waving banners baring anti-Trump messages.

In Denver, protesters managed to shut down Interstate 25 near downtown Denver briefly Thursday night.

Denver police tweeted around 10 p.m. that demonstrators made their way onto the freeway and traffic was halted in the northbound and southbound lanes.

Police say the interstate was reopened about half an hour later as the crowd moved back downtown.

Earlier protests in Denver, Boulder and Colorado Springs on Wednesday and Thursday went off peacefully.

In San Francisco’s downtown, high-spirited high school students marched through, chanting “not my president” and holding signs urging a Donald Trump eviction.

They waved rainbow banners and Mexican flags, as bystanders in the heavily Democratic city high-fived the marchers from the side-lines.

Hundreds of protesters demonstrated outside Trump Tower in Chicago and a growing group was getting into some shoving matches with police in Oakland, California.

Another protest was building in Los Angeles, where 28 people were arrested Wednesday for blocking traffic during a demonstration that also saw vandalism to some buildings and a news truck. (Fox News)

•Photo shows anti-Trump protesters.

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