[Nateman]

There was a security video of the collapse. I noticed in the first second of the collapse a bunch of bright flash's on one floor. Was this from Sparks of electric lines getting shorted or something more ominous

[Texas Fossil]

As the building shattered the power circuits broke and shorted. I saw the video. The flashes happened in a number of places. It was a sickening thing to see. No explanation was necessary.

Later the the video’s of the inside looked like hail falling as the ceilings began to shed particles before the collapse.

[proud American in Canada]

Yes. And the moment the light went out in the second one, it collapsed.