If it\'s an accident, the odds are astounding.
Consider that the engine actually seperated from the plane.
First off, to have an engine fire is not that unheard of. That said, there are redundant (several) fire extinguish systems Per Engine that are activated either automatically or manually by the crew.
Now, *if* this engine did catch fire, the chances of all fire retardation systems failing, and the fire burning so out of control as to actually cause the engine to seperate from the plane is so coincedental and mathmatically astounding that I personally find it hard to believe.
It could have happened like that, but I find those odds extremely high. Personally I think it was sabotaged.