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: intelligence on orders for the 3rd anti-aircraft Brigade to move to Romania for operations in the Ploesti area, and that anti-aircraft defence in Romania and Bulgaria was to be subordinated to the 10th Anti Aircraft Division; aircraft mines for use in the Black Sea were reported to be unusable; an order to the Aerodrome Regional Command in Zagreb that cement not steel bombs were to be used in operation GYPSY BARON, and would be supplied by German Air Force (GAF) Equipment Group 17; an evening report from the 1st Panzer Group on September 19 that Soviet attacks on the Piryatin-Lokhvitsa road were repulsed, and local resistance was met elsewhere; a German report on shipping movements in the Mediterranean on September 18, stating that the Pietrino convoy was attacked, the auxiliary vessel Filuccio sunk, a large convoy was reported being assembled in Gibraltar for the Mediterranean, and the Vulcania arrived in Tripoli on September 18; and a circular from the 5th Air Fleet to various authorities in Norway describing Soviet phosphorous incendiary bombs, and the method of dealing with them.