December 4, 1941
Re my #867. [a]
Before you burn the codes brought you by KOSAKA, have him teach all your telegraphic staff how to use them. If you have not yet burned the keying described in my Circular #2400 [b], keep it in your custody until the last moment. Moreover, send it by some suitable plane to our ministry in Mexico in care of Junior Secretary MATSUI or Secretary NAGAKI in San Francisco or some other suitable courier. Wire this to Mexico and let me know what reply they make.
Army 25754 Trans. 12-4-41 (S)
[a] S.I.S. #25640 which gives instructions regarding the destruction of codes.
[b] See S.I.S. #25753.
(EXHIBITS OF JOINT COMMITTEE , EXHIBIT NO. 1 INTERCEPTED DIPLOMATIC MESSAGES SENT BY THE JAPANESE GOVERNMENT BETWEEN JULY l AND DECEMBER 8, 1941)