Joaquin Phoenix and Martin Sheen have been arrested after taking part in Jane Fonda's final Fire Drill Fridays climate change protest in Washington, D.C.
The Barbarella actress and activist boasted one of the largest crowds to date this week on January 10 as she staged the last of her events in the nation's capital, as she prepared to take the weekly march to California.
Phoenix served as one of the guest speakers at Friday's rally, encouraging attendees to join him in going vegan in a bid to help save the planet.
Introducing the Joker star to demonstrators, Fonda revealed Phoenix had come "of his own volition" to address fellow activists, after delivering a similar message onstage at the Golden Globe Awards last weekend January 5.
"Something that oftentimes isn't talked about in the environmental movement or in the conversation about climate change is that the meat and dairy industry is the third-leading cause of climate change," he said.
"I think sometimes we wonder, 'What can we do in this fight against climate change?' And there is something you can do today, right now, and tomorrow by making a choice about what you consume."
"I struggle so much with what I can do at times," he continued. "There are things I can't avoid. I flew a plane out here last night, but one thing I can do is change my eating habits. So I just want to urge all of you to join me in that."
Shortly after he took to the podium, police officers warned protesters to disperse or risk arrest, and when Phoenix failed to oblige, he was taken into custody, alongside 79-year-old Sheen, Fonda's co-star on TV hit Grace and Frankie.
Actress Maggie Gyllenhaal was also in attendance, although she was not detained, while Susan Sarandon and Amber Valletta were previously expected to join in, too.
Fonda launched the Fire Drill Fridays protests in early October, and has been arrested for civil disobedience a handful of times.
She was not among those busted on Friday, but Phoenix and Sheen are in good company, as fellow celebrities Sally Field, Ted Danson, Sam Waterson, Lily Tomlin, and Rosanna Arquette have all found themselves in handcuffs after marching alongside Fonda.
Fonda will hold her next batch of Fire Drill Friday events in Los Angeles, starting on February 7, as she returns to work on the set of Grace and Frankie.