A 22-year-old man who identified himself only as Lou said he has spent almost his entire life in Oakland and supported the protests.
"Ever since the Black Panthers we've been protesting — this is not new," he said. "... These protests have been around for forever. This is how you make change."
But describing the scene — "a bunch of officers, riot gear on; a bunch of smoke; trash cans on fire; sirens everywhere; graffiti everywhere" — he called it "just tragic."
Tiffany Walker-Roper said she didn't intend to attend the protest but did so after being delayed in leaving downtown Oakland.
"I decided to stay because this cause is extremely important," Walker-Roper said. "... Black people are just out here trying to survive, and we're tired. We're tired of watching our people get killed. We're tired of the lack of opportunity in our communities. We're tired of these systemic injustices that have created these situations where people who are supposed to be serving and protecting are murdering and maiming."
Michael Houston, who said he moved to Oakland from New York City three years ago, said the protest brought him back to Black Lives Matter in his East Coast hometown.
"It's the same thread that's been occurring since the civil rights movement, since slavery — the inhumane treatment of black people around the world," Houston said.
He said that when he saw the wall of police officer clad in riot gear, he wanted to ask them, "What do you think of this situation? Regardless of your job, what do you think in a moral position, of what's happening. And really have a face to face conversation."
Separately Friday night, Oakland police said they were investigating the shooting of two security guards near the intersection of 12th and Clay streets. Although demonstrators were near the corner at the time of the shooting, police said in a tweet that they did not believe the incident was related to the protest.
Prior to the confrontation outside police headquarters, dozens of protesters used the Jackson Street onramp to get onto Interstate 880. Traffic on the freeway was halted in both directions for about half an hour.