at iHeartRadio Festival
9/22/2012 5:08 AM PDT BY TMZ STAFF
Green Day front man Billie Joe Armstrong did not take kindly to having his set at the iHeartRadio Music Festival cut short last night in Las Vegas ... so he went on an expletive-laden rant on stage before smashing his guitar and storming off.
According to reports, the show was running 25 minutes behind schedule and rather than let the show run longer, organizers decided to cut down Green Day's set.
When given the one minute warning, Armstrong went ballistic, screaming, "I'm not Justin Bieber, you motherf**kers! You gotta be f**king joking. I got one minute, one minute left. Now I got nothing left. Let me show you what one minute f**king means" ... before slamming his guitar into the ground.
It's unclear why Armstrong invoked Bieber's name -- he didn't perform last night and is not scheduled to appear at the festival tonight either.
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