The Phoenix Fire Department in Arizona has launched an investigation into the cause of the massive bonfire that was started during a Slipknot concert at the Ak-Chin Pavilion on Tuesday (Nov. 2), which forced the band to pause their set to allow the blaze to be extinguished.

Footage of the inferno circulated on social media yesterday (Nov. 3), where fans piled up lawn chairs and set them on fire, adding more to the stack as Slipknot performed "All Out Life." As a result of the half-hour delay as the fire was dealt with, the band cut two songs — "Duality" and "Spit It Out" — from their set, which had been constants throughout the Knotfest Roadshow trek.

A spokesperson for the Phoenix Fire Department told Arizona Republic that Engine Company 40 "responded to the pavilion and found a large contents fire... possibly started by bystanders at the event."

"The fire was thoroughly extinguished without any extension to the major structure and no injuries were reported at the incident," the spokesperson continued, and added, "The exact cause of the fire is currently under investigation and no persons were displaced at this incident."

The Phoenix stop was the last date of the Knotfest Roadshow run, which also featured Killswitch Engage, FEVER 333 and Code Orange. Up next is Knotfest Los Angeles tomorrow (Nov. 5) at Banc of California Stadium with the three aforementioned support acts as well as Bring Me the Horizon and Cherry Bombs, the dance, pyro and aerial stunt troupe.

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