Far East Combined Bureau

The Far East Combined Bureau, an outstation of the British Government Code and Cypher School, was set up in Hong Kong in March 1935, to monitor Japanese, and also Chinese and Russian (Soviet) intelligence and radio traffic. Later it moved to Singapore, Colombo (Ceylon) and then Kilindini (Kenya).

The FECB was located in an office block in the Naval dockyard, with an armed guard at the door (which negated any attempt at secrecy). The intercept site was on Stonecutters Island, four miles across the harbour, and manned by a dozen RAF and RN ratings (plus later four Army signallers). The codebreaking or Y section had Japanese, Chinese and Russian interpreters, under RN Paymaster Arthur (Harry) Shaw, with Dick Thatcher and Neil Barnham. The FECB was headed by the Chief of Intelligence Staff (COIS) Captain John Waller, later by Captain F. J. Wylie.

Shaw had been dealing direct with GC&CS and the C-in-C Far East in Shanghai, but found that Waller expected that everything should go through him, and paid little regard to keeping sources secret. So by 1936 the two most senior naval officers were barely on speaking terms. Colonel Valentine Burkhart found when he arrived in 1936 that the bureau was involved in “turf wars”, although they eventually accepted that they had no control over the use of intelligence reports.

Initially the Y section was to focus on the three main Japanese Navy codes and cyphers, the Japanese Naval General Cypher, the Flag Officer code and the “tasogare” or basic naval reporting code used to report the sailings of individual ships. In 1938 a section was set up to attack Japanese commercial systems and so to track supply convoys. From 1936 many messages were sent back to London, to be deciphered by John Tiltman, who broke the first version of JN-25 in 1939.

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