Well, it certainly could have been a crew member...either in the cockpit or with access to it.
I think they still need to REALLY check those other two African airports this aircraft visited before flying to Paris for this final flight to Egypt.
Someone at one of those facilities, which are probably not nearly as tight as Paris, could have introduced something.
Either way, I personally believe it was an act of terrorism.
Agree 10,000% it was terrorism.