Slipknot announced today (June 30) that guitarist Jim Root is missing tonight's kickoff show of the band's headlining stint on the Rockstar Energy Drink Mayhem Festival tour because of a burst appendix that "could have been life threatening."

The band reports that Root (aka #4) has been seriously ill for the past few weeks, and recently went to the hospital where he found out that his appendix had burst. He is likely to miss additional Mayhem shows, but the band hopes he can get back onstage as soon as possible.

The Rockstar Energy Drink Mayhem Festival also features Slayer, Motorhead, Anthrax and a host of other metal bands. It kicked off today in San Bernardino, Calif. Slipknot's full statement on Root reads as follows:

We're sorry to announce that our brother, Jim Root, will not be performing with us at Mayhem today in San Bernardino due to serious health issues. Jim has been seriously sick for the past two weeks and went to the hospital last week where he was advised that his appendix burst a couple weeks before and that it could have been life threatening. Jim is at home recovering and is awaiting surgery to have pieces of his appendix removed and hopes to join the tour as soon as he is able. Slipknot will continue to headline the Mayhem Festival and all other shows. We refuse to let our fans down and will not miss a single date. We will miss Jim greatly and our thoughts are with him. Jim sends his love to each and every one of our fans.

-Slipknot

Loudwire has a reporter at tonight's Mayhem festival, and we will keep you posted on any further news involving Jim Root's condition. In the meantime, we wish him a speedy recovery.

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