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: a 10th Air Corps report of air raids on Tobruk on May 27-28; a report and orders from Kesselring for May 27-28; that the Panzer Army is requesting urgent support of a strong Stuka attack on May 29; and a report for May 28 on north west Europe and the northern sector of the Russian Front including a report of an attack on convoy PQ 10.