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 Southern Europe: that the German 362nd Division at the Anzio bridgehead fails to obtain fighter support to destroy Allied artillery spotter aircraft which were making entrenchment impossible during daylight hours, on March 17, because all German Air Force (GAF) support was being committed to the Cassino area; and a detailed summary of the guerrilla situation in Yugoslavia for March 16/17, covering that the Germans wiped out a store of U.S. weapons west of Split; on the German Navy: on the serviceability of the Tirpitz after work-up trials on March 15 and 16, with a final dockyard conference to be held on March 18; on the Russian Front: that GAF and Romanian Air Force units are to mount maximum effort air strikes against Russian forces advancing across the rivers Bug and Dnestr, on March 18/19; and Naval Headlines.