The LAPD said the march remained peaceful and no one was arrested.
Several dozen of the protesters rallied at Pershing Square before heading out to march. Many were upset about the police's use of force during a clash the night prior.
"I mean, honestly, shooting rubber bullets at anybody, what would justify that? It would have to be a pretty extreme attack to justify that," said Occupy L.A. protester Lee Camp. "And I haven't even heard anything that resembles that, but I have seen photos of kids who were hit with rubber bullets."
The trouble started just before 9 p.m. Thursday when a crowd started filling the area around Fifth and Spring streets. Occupy Los Angeles protesters were in downtown for a "Free Chalk for Free Speech" event to show support for people previously arrested for chalking on the sidewalks. The event was not sanctioned by authorities, so it caught them by surprise. Police in riot gear broke up a crowd of about 200 people.
Authorities said some of those people threw rocks, bottles and other objects at officers. Police, who were on citywide tactical alert, responded with rubber bullets on the crowd.
"I was just here for Art Walk. I didn't know anything was going to happen. I walked toward a group of people, and I see the police, so I turn around because I don't want to get in trouble, and they ... shot me in the chest. I fell to the ground," said witness Charlie Shepard.
Police dispersed the crowd by midnight. Seventeen people were arrested, four of them for assault with a deadly weapon on a police officer and resisting arrest. Four police officers were injured during a clash with protesters. The officers were taken to a local hospital to be treated for minor injuries.
Crews were out early Friday morning cleaning up the mess, while residents found themselves wondering how it all got out of control.
"I think Occupy kind of took advantage of Art Walk and the huge crowd and made it seem like more of a protest and got the police kind of scared and upset," said Sarah Godshaw, a Downtown L.A. resident. "It was really scary, just as a spectator."
The vandalism stretches across several downtown blocks. While most of it is in chalk, spray paint was also used. Some business owners are worried that lasting damage has been done to the reputation of the area - an area they are trying to turn around.