Smoke filled the air outside a police precinct in Portland, Oregon early on Saturday, as authorities worked to clear a crowd accused of damaging patrol vehicles, throwing projectiles and pointing lasers at officers.

Police declared a riot outside the department’s north precinct. Smoke was deployed and officers forced protesters away from the area, news outlets reported.

Windows were broken on patrol vehicles, police said, and items such as glass bottles were thrown and lasers were aimed at officers. Videos posted online showed several people being detained after the riot declaration, but it wasn’t immediately clear how many arrests were made.

Demonstrations – some violent, the majority peaceful – have taken place in Oregon’s largest city for more than two months, following the death of George Floyd in Minneapolis police custody in late May.

Across the US, such protests have sought reform to address police brutality and systemic racism and inequality.

On Saturday morning, from the White House, Donald Trump lamented “another bad night of Rioting in Portland, Oregon.”

Trump’s decision to send federal agents to confront protesters caused huge controversy, as the president seeks to run for re-election on a law and order platform.

“A small number of Federal troops there to protect courthouse and other Federal property only (great job!),” Trump wrote on Saturday. “Wanting to be asked by City & State to STOP THE RIOTS. Would bring in National Guard, end problem immediately. ASK!”

Early on Friday morning, protesters clashed with federal agents outside a US Immigration and Customs Enforcement building in Portland. People in a group of about 100 sprayed the building with graffiti, hurled rocks and bottles at agents and shined laser lights at police, officers said.

The agents set off smoke or tear gas and used crowd control munitions to try to disperse the crowd. Three people were arrested.

Also on Friday, a number of federal buildings across the city were closed as the FBI investigated a car bomb threat.