12 hours ago, DMD said:
Probably ignited the residue of a million beer farts
I saw a story saying the fire started in a lounge/suite, possibly by workers doing metal work in the lounge area. Fire then spread to the seats on the level below it I’d suspect thru some type of ventilation system. Seats were apparently flammable (petroleum based) flames move easily with some wind, causing it to spread from seat to seat. The sprinkler system came on, and probably stopped or slowed the spread until fire fighters could get to it.
According to the story some events were going on inside the venue and people were evacuated.
https://kdvr.com/news/local/large-plume-of-smoke-at-empower-field/