You can just say explosion, we're not at the Cape.

Which is a sub-class of anomaly :-) it is really hard to scrub Youtube videos, and I (like probably a zillion others) was looking for root cause indicators; things like where exactly on the fuselage does it start? What equipment is there? How energetic was the explosion (oxidizer only? mixed with propellant? Etc. There are at least 30 frames between 1:10 and 1:11 (maybe 60). There are many things to rule out, was it a leak in the LOX hose? Was it a rupture of an internal tank? did the equipment detach prematurely? etc etc.

> it is really hard to scrub Youtube videos

    pip install youtube-dl

https://rg3.github.io/youtube-dl/