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: 912T23 is not included; on the Mediterranean: an Italian naval report of April 20; on the Mediterranean and North Africa: on German Air Force (GAF) operations and recce for April 21-22; on the Southern Russian Front: a GAF report on enemy raids on April 14-20 (a bridge was hit); and on German fuel delivery problems because of the flooding of railways, on April 21.