Two days after Green Day lead singer Billie Joe Armstrong had a mental meltdown on stage at iHeartRadio Music Festival, he has checked into rehab.

His rep told E!: “Green Day’s Billie Joe Armstrong is seeking treatment for substance abuse.” The rep added, “Green Day would like everyone to know that their set was not cut short by Clear Channel and to apologize to those they offended at the iHeartRadio Festival in Las Vegas. The band regretfully must postpone some of their upcoming promotional appearances.”

Billy Joe spiraled into a profanity-laden rant after being given a “one minute warning” to finish the band’s set. He flipped off the camera and smashed his guitar as he kept yelling, “You’ve gotta be f–king kidding me! You’re f–king kidding me. What the f–k! I’m not f–king Justin Bieber, you motherf–kers…I got one minute—one minute left.” Watch his rant here.