Slayer's Jeff Hanneman has a flesh-eating disease.
Hanneman is believed to have contracted the rare necrotizing fasciitis after a spider's bite. The condition, which eats away at fat, tissue and skin, will see the guitarist undergo surgery on his right arm shortly in a bid to stop the disease spreading.
The band have confirmed they will still honour their touring commitments and will draft in a replacement for the stricken guitarist in the coming days.
Slayer are set to play this year's Sonisphere, along with Metallica, Biffy Clro and Slipknot.