Footage of the violence, which erupted between the supporters and opponents of US President Donald Trump, has appeared on the Internet, according to the Los Angeles Times.
The clashes occurred in Huntington Beach, California.
A brawl sparked between them after a protester opposed to Trump allegedly doused a female organizer of a pro-Trump rally with pepper spray.
Two people were injured in clashes.
Police dispersed the crowd, and arrested six opponents of the US president.
