UPDATE: Billie Joe Armstrong is entering rehab for substance abuse following his meltdown on stage at Friday night's iHeartRadio Music Festival. 

The statement from Green Day's official website:

'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.'

CLICK HERE FOR FULL IHEARTRADIO MUSIC FEST NIGHT 1 RECAP

Probably the most memorable moments of the iHeartRadio Music Fest (not for the best reasons) was the meltdown of Green Day lead singer Billie Joe had after claiming to be cut short on time.

At one point Billie Joe yells 'I'm not f**king Justin Bieber you motherf**kers'

WARNING: EXTREMELY EXPLICIT LANGUAGE IN VIDEO