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 above Silvermaster and was in contact with MGB officials of the New York Soviet Consulate. We have an active investigation in progress to identify Albert, and he will undoubtedly prove to be one o the unidentified principals of Bentley, whom we have not been able to identify based on the information provided by her.

You will recall that we have conducted an extensive investigation in the Lydia Altschuler, was., etal, Internal Security — R case concerning an espionage network involving cipher messages in secret ink exchanged between persons in the New York City area and persons in Mexico City and South America. The secret ink messages dealt primarily with the efforts of the espionage parallel to free Frank Jacson, Trotsky's killer, who was imprisoned in Mexico City. You may recall that there were eight messages in the Altschuler traffic which we were never able to decipher because we could not find the book used in the encipherment. From information we identified this book as "Una Excursione a Los Indios Ranqueles," a paper-bound edition published in Argentina. Through this identification our Cryptographic Laboratory has just finished the decipherment of seven of the eight remaining messages intercepted in the Altschuler case. These messages extend the ramifications of the espionage parallel we knew in the Altschuler case and one message shows the network was, in 1943, setting up a radio station in Argentina. One of the messages sets forth that the same code was to be used by the station as in the Altschuler case, and gives the frequency to be used and the time of intended operations. We are to attempting to develop whether there is in existence traffic intercepted from such a station. There is some indication that such traffic will be in existence available through either the Armed Forces Security Agency or the FCC.

It is also of considerable interest to note that the radio stations set up at the Soviet Consulates in New York City and San Francisco transmitted messages in code, and among the intercepts available in connection with these two transmitters there have been found intercepts of a station operating on at least one of the frequencies and using one of the call letters set forth in the secret ink messages. A preliminary examination by our Cryptographic Laboratory indicates that we will be able to decipher at least one of these messages, but it is not possible to accurately predict whether we will be able to tie this in with the South American station. As soon as the Cryptographic Laboratory finishes their work this entire matter will be reviewed and analyzed for you and submitted to the Field for further investigation.