notable
>>8753175 Explosion at electrical substation in Burbank, California
That appears to be something like petroleum fuel exploding and burning. Nothing in an electrical substation would burn like that. Look at the fireball and subsequent very thick heavy black sooty smoke.
I vote for sabotage.
Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent electrical insulating properties. It is used in oil-filled transformers, some types of high-voltage capacitors, fluorescent lamp ballasts, and some types of high-voltage switches and circuit breakers. Its functions are to insulate, suppress corona discharge and arcing, and to serve as a coolant.