A feud between Elon Musk and Mark Zuckerberg has seemingly escalated, with both CEOs teasing the possibility of an actual physical fight. Meta reportedly has an upcoming Twitter competitor, which may have ruffled Musk’s feathers.

Following a story about Meta’s rumored Twitter competitor, Musk tweeted about being “up for a cage fight” with Zuckerberg. Zuckerberg posted a photo of the tweet on his Instagram story and said “send me location.” Meta apparently confirmed to “The Verge” that Zuckerberg’s response was not a joke, with Meta spokesperson Iska Saric saying “The story speaks for itself.”

Musk has replied with two words: “Vegas Octagon.” Zuckerberg has been learning Brazilian jiu-jitsu for about a year from Dave Camarillo, who was once the mentor for former UFC stars Cain Velasquez, Jon Fitch and Josh Koscheck, and others. It remains to be seen if the fight will actually get scheduled.