After more than a decade together and some 13 million albums sold, Chicago heavy hitters [artist id="760710"]Disturbed[/artist] are preparing for an "indefinite hiatus," according to frontman David Draiman.

Draiman announced the news on his Twitter account, in response to a fan's question about rumors that the band was breaking up. And while he admitted that he has no idea what Disturbed's long-term plans are, their immediate future is pretty clear: "We haven't said that were breaking up. We simply do not know yet," Draiman wrote. "All I can say is we are going on an indefinite hiatus."

He added that he "can't really get into the reasons" why Disturbed were planning on taking a break, and wrote, simply, "Let's just say it's time." Draiman was equally mysterious about his future plans, writing that even if he wasn't singing with the band, he would "always be involved in music on some level."

Disturbed are currently touring North America with Godsmack and Megadeth on the 2011 Mayhem Festival, which wraps August 14 at the Cruzan Amphitheatre in West Palm Beach, Florida. They have a handful of South American dates scheduled for the end of the month, and then, as Draiman put it, the band is "done."

A spokesperson for the band could not be reached for comment by press time.

In an interview with Dallas radio station KEGL on Wednesday, Disturbed guitarist Dan Donegan clarified Draiman's remarks, saying, "Ever since the start of this band, we've always had a game plan of what comes next after each thing. So it's always been 'write, record, tour, let's go home for a month, let's start writing again, do the same thing all over again.' ... This time around, we just haven't really gotten to those discussions yet. We know that we're coming to the end of this touring cycle and we just haven't planned on what we wanna do next."

And, much like his frontman, Donegan didn't seem to have an idea about just when (or if) Disturbed would ever play together again, but added that the focus right now is to end things on a high note.

"I don't have a clear answer [about the band's future], because I'm not sure where everybody's head's at at the moment other than we're having a great time out on tour, we're going out big, we're carrying big production, we wanna end this on a big note," he said. "I think we're not ready to sit down and have the discussions of when we wanna get back together or if we're gonna. So we're kind of winging it."

Disturbed formed in Chicago in the late 1990s and broke through to the mainstream with bludgeoning hits like "Stupify" and "Down With the Sickness." They have released five studio albums, the last four of which -- 2002's Believe, '05's Ten Thousand Fists, '08's Indestructible and last year's Asylum -- each debuted at #1 on the Billboard albums chart.

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