There were pools of molten iron so hot that it remained molten for three weeks after the collapse. I'm surprised more people don't advocate for DEW or nukes as the source of such fierce heat.

Only thermite and thermate could have produced that energy, likely due to excess reactants that kept reacting in the pools below ground.

Kerosene, office chairs, and pristine passports didn't fuel that underground hell, but the fire below still burned.