Rally Held in Oakland in Support of Portland Protesters (+Video)

The event began at 7:30 p.m. at Frank H. Ogawa Plaza at 14th Street and Broadway in Oakland, according to organizers which included the Wall of Moms Bay Area, Refuse Fascism Bay Area and Vigil for Democracy.

The Wall of Moms group encouraged participants to wear yellow and bring sunflowers. All must wear masks to prevent the spread of COVID-19.

"Reject secret federal police in our cities, and celebrate our right to gather peacefully and protest," the moms' group Facebook page says.

Crowds were seen marching through downtown Oakland.

The Oakland Police Department partially opened their Emergency Operations Center Saturday afternoon to monitor the protest, Officer Johanna Watson said. The Alameda County Sheriff said it will be standing by if mutual aid is requested.

Officials tweeted that some people within the hundreds of demonstrators vandalized the police station by breaking windows, spray painting and shooting fireworks.

Federal officers were sent by US President Donald Trump to protect federal property in Portland, but their presence has escalated tensions and drawn several other groups to the protests.

Wall of Moms groups formed in recent weeks after Trump announced he was sending federal troops to Democratic-led cities.

In Seattle, thousands of protesters initially gathered near downtown on Saturday in a show of solidarity with fellow demonstrators in Portland.

Seattle police declared a riot following large demonstrations in the city's Capitol Hill neighborhood and deployed flash bangs and pepper spray to try to clear an area near where weeks earlier people had set up an "occupied protest zone" that stretched for several blocks.

Via Twitter, police said they had made some arrests Saturday and were "investigating a possible explosive damage'' to the walls of the city's East Precinct police station.

Authorities said rocks and bottles were thrown at officers. More than two dozen people were arrested.