Majestic 12, MJ-12, Majic-12 (The Space Alien Hoax)

The Majestic Twelve Documents are a set of documents that purported to reveal a secret committee of 12, supposedly formed in 1947 by an executive order by U.S. President Harry S. Truman1. The documents detail how the crash of an alien spacecraft at Roswell in July 1947 had been concealed, how the recovered alien technology could be exploited, and how the U.S. should engage with extraterrestrial life in the future1. The documents also list the members of the government's special Majestic-12 or "MJ-12" UFO group.

https://en.wikipedia.org/wiki/Majestic_12
https://ia800500.us.archive.org/35/items/majestic-12-documents-for-majic-eyes-only/Eisenhower%20Briefing%20Document_text.pdf

Alleged members
The following individuals were described in the Majestic-12 documents as "designated members" of Majestic:

Lloyd Berkner
Detlev Bronk
Vannevar Bush
James Forrestal
Gordon Gray
Roscoe H. Hillenkoetter
Jerome Clarke Hunsaker
Donald H. Menzel
Robert M. Montague
Sidney Souers
Nathan F. Twining
Hoyt Vandenberg

https://archive.org/details/majestic-12-files