Condolences to all involved in what looks like a very miserable event indeed. Normally, I'd add "and there's no point in speculating before some more information is in." (well, normally I wouldn't say anything).
However, I think there is a valid and immediate concern over the way the Egyptian authorities reacted. Either they have some solid information about a catastrophic failure in this most popular aircraft which they are not making known as widely as they could, or they are so desperate to make people think it can't be terrorism that they are prepared to massively distort their proper role in sorting out what happened.
Perhaps there's a third option I've missed?
R