Why spies still use WW1-era encrypted radio broadcasts

Sunday Extra - Separate stories podcast · Mar 21, 2026 · 16m

Short-wave radio enthusiasts have eagerly reported the appearance of Farsi-language encoded messages being broadcast out of Western Europe. The messages are being transmitted via number stations, which are radio broadcasts used by intelligence agencies to send encrypted messages to agents in the field. It is one of the oldest forms of clandestine communication, dating back to the first World War, and is still used by modern intelligence agencies today because they're almost impossible to decipher.