No whistling, no multicolored effects, no 100yard launches and report. That looks like ordinance cooking off.
Yeah, there may have been fireworks in there.....and they may even be responsible for the initial fire......but that big explosion was not simply the detonation of a bunch of fireworks. I heard the same as mentioned above - 2750 TONS of ammonium nitrate. For perspective, the OKC bombing was 2 tons...