The circumstances behind Green Day's Billie Joe Armstrong, 40, being rushed to the hospital for an undisclosed ailment in Bologna, Italy, earlier this month might have just gotten a little bit clearer, as he checked in to a rehab facility over the weekend.

Armstrong is currently "seeking treatment for substance abuse," said his publicist, Edna Gundersen, reports USA Today. The treatment may be connected to Armstrong's public meltdown on Friday night at the iHeartRadio concert in Las Vegas, when he thought that the Green Day set had been cut short to provide more time for Rihanna and Usher to perform.

After reportedly seeing that they were being given a one-minute signal, Armstrong lost his cool on stage, smashing his guitar and yelling a stream of obscenities.

"You've gotta be (expletive) kidding me! You're (expletive) kidding me. What the (expletive) I'm not (expletive) Justin Bieber, you mother-(expletive) … I got one minute—one minute left," he reportedly said.

A statement later released by the band revealed that the whole thing was a misunderstanding. "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."

Green Day is set to release their next studio album, Uno, on Tuesday. They are slated to kickstart their tour for the album in November.

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