A protest and "die-in" in downtown Oakland involving a reported 1,000 people led to a traffic-snarling march onto the I-580 freeway Monday night, as Bay City News reports. The protesters came out in force following the grand jury decision in Missouri not to indict the police officer, Darren Wilson, involved in the August shooting death of unarmed 18-year-old Michael Brown. It's unclear how many protesters ultimately made it onto the freeway, but as of 9:15 p.m. ABC 7 was tweeting that "dozens" of them had brought traffic to a halt.

Live on the air at 11, ABC 7 reported that "500 or so" protesters were involved in the freeway march, after marching up the Lakeshore on-ramp. Some had signs that said, "The People Say Guilty."

Some 700 police officers were reportedly on the ground in Oakland, many of them trying to hold a line on the freeway. As of 11 p.m., 580 was was apparently clear of protesters and traffic was moving again, but bonfires were starting in the middle of city streets, including one at Grand and Macarthur. Also, a separate protest continued near Oakland Police headquarters on Broadway in downtown Oakland involving firecrackers, a bonfire, and at least 100 officers were trying to hold a line there. The Chron's Vivan Ho was on the ground and reported looting at a nearby Starbucks. As with protests in the past in Oakland, one can probably expect more chaos over the next couple of hours.

The shooting of unarmed civilians by law enforcement remains, of course, a sore subject in Oakland just five years after the killing of Oscar Grant. But across the nation, simultaneous protests were also occurring Monday night in Seattle, Los Angeles, Chicago, New York, and Philadelphia. In New York, the police commissioner had fake blood thrown on his face by a protester. And fires and protests continue angrily into the night in Ferguson, MO, as well, with reports of at least 100 shots fired.