Government Code and Cypher School: Signals Intelligence Passed to the Prime Minister, Messages and Correspondence

A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following reports on North Africa: that German Air Force (GAF) night fighters are to be used for local defence and over Egypt on April 22; on the Southern Russian Front: of GAF operational orders for April 23; on the Mediterranean: of GAF operations and intentions for April 23-24; and that the 10th Air Corps' operations directorate is to operate from Crete from April 25.