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"Beastie Boys regret that Adam 'MCA' Yauch will be unable to join Mike 'Mike D' Diamond and Adam 'Ad-Rock' Horovitz at the band's induction into the Rock n Roll Hall of Fame," read an official statement released hours before the event.
No word yet on what led to the no-show, though Yauch has kept a low profile since 2009, when news broke of his battle with cancer of the salivary gland.
"Mike, Adam and Adam are truly grateful for the honor but with only two of the three Beastie Boys attending, they will unfortunately not be able to perform at the ceremony," the statement continued.
In their acceptance speech, Mike D and Ad-Rock read a thank-you from their absent comrade, who told fans, "This induction is as much ours as it us yours."
Public Enemy leader Chuck D had the task of inducting the Beasties, and in his speech, he praised the group for breaking down boundaries and widening hip-hop's appeal.
"It broke the mold," he said. "The Beastie Boys are indeed three bad brothers who made history. They brought a whole new look to rap and hip-hop. They proved that rap could come from any street -- not just a few."
The 2012 Rock Hall Nominees