Privéoy¥ AQT MAPEMUPhen ‘ oo 5 * X HRADOUARSERS.. APO 187, c/o Postmaster. - San Francisco, California SUBJECT? «Security Letter: Po a TO, win So. ee - get Sole " TASK GROUP 7,4, PROVISIONAL oe \ . 7 . | ; Rode oy . Avy 5 March 1954 0 Cs oO “ fase my ea Au Personnel 1. Information concern the detonation of the first ina serles of - tests 1s classified CONFIDENTIAL, except for that which has been officially announced in the two (2) AEC releases, dated 9 January 1954 and 1 Marcha» 1954 as quoted below: 1st Release - 9 January 1954 "During this month men and material will begin moving to the Pacific Proving Grounds of the Atomie Energy Commission to carry out a further phase of a continuing series of weapons tests of all categories, These tests are part of the Atomic Energy Commission 2 research program for the improvement of weapons, pursuant to — so its responsibility under the AEC Act, These tests will be conducted . by Joint Task Force Seven (JIF 7), commanded by. I US officials. _ 1, USA, There will be no observers other, than Pape » SILIIE PK, 2ndq Release - 1] March 1954 "Louis E, Strauss, Chairman of the United States Atomic Energy Commission announced today that Joint Task Force SEVEN has detonated an atomic device at the Atomic Energy Commission's Pacific Proving Grounds in the Marshall Islands, This detonation was the first in a series of tests," 2. The fact that an official release was made regarding the "First detonation in a series of tests," autamtically downgrades that portion of informtion to unclassified, HOWEVER, it is desired that no reference be made to this first detonation in letters home. 3,~—Let the folks back home gain their information through the newspapers, radio and TV, regarding our work here in the Pacific Proving Grounds. By doing this, there is no possibility of you becoming involved in a security leak through misinterpretation of what is classified and what is not classified, BY ORDER OF THE COMMANDER, _ TAB NO. 27