C-SAR,
The only other cases of fragmentation to this extent without any fire damage that I can remember, are the Avianca 707 at New York, and the United DC-8 at Portland. There is supposed to be adequate fuel onboard for diversion but still, the margins are not extensive and a math error can still happen. Even though this flight takes place within African borders, it's a long flight, nearly 9 hours. That's also a long time in which to make errors in fuel management. But in any case the complete lack of soot is very telling.
-drl