Well, yes they are but, they are demons and can appear looking just like us we know this from the Book of Genesis Adam and Eve, and we know this from the book of Job. Demons can appear to us as any appearance like animals or like us man. I try not pay attention to man words like UFO fly aircraft, demons teach man how to build Weapons of mass destruction, so yes demons can build UFO flying aircraft. They can build anything that man can build in order to Deceive the world.
Agreed. Your viewpoint puts a different tilt on the question, steering towards things native to this world as opposed to other planets.