Mike Portnoy, drummer of progressive metal band Dream Theater, jolted his fans worldwide Wednesday night by announcing his departure from the band he founded.

Portnoy is currently the touring drummer for Avenged Sevenfold, which will perform as part of the Rockstar Energy UPROAR Festival this Friday in Dallas and Saturday in Corpus Christi. Several months after the death of Avenged drummer Jimmy "The Rev" Sullivan last Dec. 28, Portnoy was asked by Avenged Sevenfold to finish the drum parts on their album Nightmare, which was released July 27. Portnoy was selected because he was one of Sullivan's idols. Portnoy then accepted the opportunity to tour with the band.

Portnoy has juggled side projects and tribute bands while in Dream Theater. His announcement leaves open the possibility that he will become more than an interim drummer with Avenged Sevenfold.

I interviewed Portnoy on June 11, the day before he did a 90-minute in-store autograph signing at Sam Ash Music. That evening, Dream Theater opened for Iron Maiden at a sold-out AT&T Center. During our interview, Portnoy said the guys in Avenged Sevenfold "welcomed me to the family." Read the rest of our interview here.

In a lengthy letter to fans on his Facebook page Wednesday, Portnoy stated in part: "I am about to write something I never imagined I'd ever write: After 25 years, I have decided to leave Dream Theater . . . the band I founded, led and truly loved for a quarter of a century. To many people this will come as a complete shock, and will also likely be misunderstood by some, but please believe me that it is not a hasty decision. After having had such amazing experiences playing with Hail, Transatlantic and Avenged Sevenfold this past year, I have sadly come to the conclusion that I have recently had more fun and better personal relations with these other projects than I have for a while now in Dream Theater."

Within 30 minutes of Portnoy's Facebook post, 1,700-plus fans had commented. Read the rest of his statement here.

Portnoy founded Dream Theater in 1985, and the band released its debut album When Dream & Day Unite in 1989. Their most popular song is 1992's Pull Me Under. They released their 10th studio album Black Clouds & Silver Linings last year. Portnoy has won numerous awards and is recognized worldwide as one of the top drummers in any genre of music.

It remains to be seen whether Dream Theater will search for another drummer or disband. Singer James LaBrie is scheduled to release a solo album, Static Impulse, on Sept. 28.

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