Harris stepped aside as the man tried to speak and organizers tried to stop him. He was quickly restrained by several men.
While it is not uncommon for protesters to interrupt presidential campaign events to promote their causes, it is rare for them to come into such close proximity to a candidate.
An animal rights group called Direct Action Everywhere issued a news release claiming responsibility for the incident. The organization identified the man who disrupted the event as Aidan Cook.
MoveOn spokesman Brian Stewart said the man was removed from the stage and the program resumed. “He was not arrested or detained as far as I am aware,” Stewart said. Harris resumed her program afterward, Stewart and others said.
A Harris campaign spokesman did not immediately respond to a request for comment on the incident. But a prominent Harris supporter, South Carolina Democrat Bakari Sellers, tweeted: “You notice @KamalaHarris wasn’t afraid.”
Harris is one of 14 presidential candidates in San Francisco this weekend for the California Democratic Convention and other campaign stops.