The KISW 99.9 FM Pain in the Grass festival turned into a pain for Slipknot fans this past Saturday as the headliners were forced to cancel their scheduled performance due to a unspecified medical emergency suffered by drummer Joey Jordison.

After more than eight hours of bands, including Steel Panther, Mucvayne, Static X and Chevelle, unmasked members of Slipknot, including lead singer Corey Taylor took to the stage, devoid of the band’s normal elaborate stage set, to inform the crowd.

“There’s a severe medical emergency,” Taylor told booing fans “[Jordison’s] OK, though. He sends his love to everyone here, and wants you to know he wishes he could be here.”

Taylor added that the band would reschedule the show and told fans to hold onto their tickets.

“We will be back in a couple of months to make this up. I want you all to send as much love as you can to Joey Jordison,” Taylor said.

The band initially said they expected to play their Kennewick show on Sunday, but pulled out of that one also.

On Monday, the band also pulled out of all their North American shows, including gigs in Montana, Idaho, Wisconsin, Colorado, Utah and North Dakota.