Between 50 and 150 demonstrators gathered at 1 Frank H Ogawa Plaza in downtown Oakland at 4 p.m. today, responding to a nationwide call to action regarding police violence posted at www.theorganicprepper.ca on Monday.
WATCH VIDEO: Sky7 HD captures tense moment between law enforcement, Oakland protesters
The affiliations of the demonstration's organizers could not be verified, but several of the people marching carried a "Black Lives Matter" banner.
The group affected traffic at a number of downtown intersections, but were described as peaceful by the Oakland Police Department.
The CHP said that the Broadway off-ramp from northbound Highway 880 had been shut down due to protesters at around 8:30 p.m.
They have since added that on-ramps and off-ramps in the area have been affected. Officers advised drivers to expect a large police presence in the area and use an alternate route if possible.
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WATCH VIDEO: Bay Area leaders, community members discuss race relations, policing at ABC7
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