More than 100 people gathered outside a federal courthouse in Portland.

Fireworks set off in downtown Portland, Ore., on Thursday night had little to do with New Year’s Eve celebrations – and more to do with continuing the unrest that has plagued the city for nearly a year, according to reports.

Once again, city police declared a riot as a gathering estimated to be about 100 people targeted a federal courthouse, FOX 12 of Oregon reported.

"Participants have thrown multiple firebombs at officers and launched commercial grade fireworks at the Federal Courthouse and Justice Center," the Portland Police Bureau wrote on Twitter just as the new year arrived early Friday.

PORTLAND MARCHERS VANDALIZE BUSINESSES, GOVERNMENT PROPERTY: POLICE

A string of messages included a warning to those congregating in the streets.

"If you do not leave you are subject to arrest, citation, and/or the use of force," the police wrote, "including but not limited to impact weapons and tear gas."

Rioters also smashed windows and set fires in the area, Portland’s KOIN-TV reported.

Police began using pepper spray or mace against the crowd, as well as what appeared to be rubber bullets or pepper balls, KOIN reported.

Some videos shown on social media showed police officers advancing against the crowd.

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Thursday’s unrest came one day after nearly a dozen businesses and government agency headquarters were vandalized, KOIN reported.

Most of the riots in Portland have occurred since May 25, when George Floyd was killed while in police custody in Minneapolis. That same event sparked numerous other protests and rioting across the U.S.