SAN FRANCISCO — Kamala Harris was forced to leave the stage at MoveOn's "Big Ideas Forum" Saturday after a man rushed her on stage.

The 2020 Democratic presidential hopeful had finished presenting her newly unveiled pay equity plan and had begun taking questions from moderators — MoveOn's Karine Jean-Pierre and EquisLabs' Stephanie Valencia — when the long-haired man wearing a shirt and jeans walked into the spotlight and took the 2020 presidential candidate's microphone.

The audience erupted in shock, with shouts of "Hey!" as the man was detained by security.

The man was later identified by activist group Direct Action Everywhere as animal rights activist Aidan Cook, a 24-year-old from Oakland, Calif., who wanted to bring that issue of animal rights to all the candidates but wanted a “conversation” with Harris as one of the California senator's constituents.

"Thank you so much, sir, for your big idea, but we want to make sure that we are able to get through this. It's OK, folks. It's OK. People have their own big ideas," one of the hosts said, trying to placate the crowd.

Some in attendance then started chanting, "Kamala," before the lawmaker walked back on stage.

"You had a question and I want to answer it," Harris said.

Cook was part of a protest organized by Direct Action Everywhere to draw attention to Democratic candidates' support of animal agriculture and those arrested for rescuing animals from factory farms.