About 80 protesters gathered in front of the CNN building in Hollywood on Sunset Boulevard shortly after midnight Monday, chanting "No Justice, No Peace," as police declared an unlawful assembly.
A police helicopter shone a light on demonstrators as more than 100 Los Angeles police officers in riot gear converged on the crowd and began making arrests and telling people to disperse. Some officers fired less-than-lethal rounds at the crowd.
The protesters had marched down to the CNN building from Hollywood Boulevard and Highland Avenue, with some carrying signs that said "We Are All Travyon Martin."
Throughout the evening, police struggled to get a handle on pockets of protesters blocking traffic in the wake of the verdict in the George Zimmerman murder trial in Florida. The neighborhood watch volunteer was acquitted Saturday of fatally shooting the unarmed black teenager during a confrontation in February 2012.
Earlier, the LAPD called a citywide tactical alert after demonstrators blocked traffic on the eastbound 10 Freeway. The freeway was shut down from 6:30 p.m. to about 6:45 p.m.