Armstrong, who performed alongside Green Day Sept. 21 at the Las Vegas festival, stopped mid-song when the band was left with only one minute to finish its set.
"You're going to give me f***ing one minute?" said Armstrong from the stage. "…You've got to be f***ing kidding me!" When time ran out, the Green Day frontman smashed his guitar, threw his microphone and left the stage.
The band released the following statement Sept. 23 on the website GreenDay.com: "Billie Joe is seeking treatment for substance abuse. We would like everyone to know that our set was not cut short by Clear Channel and to apologize to those we offended at the iHeartRadio Festival in Las Vegas. We regretfully must postpone some of our upcoming promotional appearances."
Green Day will release its upcoming album "Uno" Sept. 25. The band was scheduled for promotional appearances on "Jimmy Kimmel Live" and "The Ellen Show," among others.