Remember that frantic caller on the Art Bell Show back in 1997? The one that said he was a former employee of AREA 51 and had just been let go on a medical discharge the week before? He tearfully and fearfully recounted (before Art's satellite feed was cut by unknown persons) that Area 51 has been infiltrated. Here is a quote:

“What we’re thinking of as aliens, Art, they’re extra-dimensional beings that an earlier precursor of the space program made contact with,”

“They have infiltrated a lot of aspects of the military establishment, particularly Area 51. The disasters that are coming, they -- the government -- knows about them. . . . and there's a lot of safe areas in this world that they could begin moving the population to NOW, Art. They are not! [doing it]

They want those major population centers wiped out so that the few that are left will be more easily controllable."
(The caller begins crying and then the satellite feed is cut)...

Here is a link: https://www.iheart.com/content/2018-04-16-remembering-art-bell-the-area-51-caller/