Officers on horseback moved to push crowds back as flash bangs and tear gas were fired into the streets. Protesters lit fireworks and chanted defiantly in response, calling on others to “hold the line”.
The protests, held in cities and towns across the United States, combined criticism of the Trump administration with calls to defend democracy and immigrant rights.
In Los Angeles, tensions have been high since immigration enforcement raids last week triggered outrage.
Authorities used crowd-control tactics to disperse the remaining protesters after the official event ended.