the justification. he is somebody that can speak on why they did it, but we don't know him as a military commander. we don't know him as a strategist. >> reporter: his face is always blurred. and his real identity or details are equally blurry. although his accent is from mainland egypt, not sinai. >> the problem is we don't actually know who he is. there are multiple theories put forward on who he might be. >> investigators have yet to pronounce on the probable or possible cause of the crash of the russian jet liner. but increase caningly intelligence officials suspect it was a bomb and the likely suspect behind it was him. for the past two years, hundreds of soldiers and policemen have been killed by him. >> it grew from a group blowing