British tanker San Girilo visited Black Sea according to a letter of the German naval attaché at Istanbul dated 6 January 1940

In his letter dated Istanbul,  6 January 1940 No. 618g. reported the German naval attaché to the Oberkommando der Wehrmacht Abteilung Ausland the ships passing Istanbul coming out of the Black Sea and loaded with contraband for or chartered by the enemy. An item mentioned the British tanker San Girilo armed with a gun at the stern manned by naval gunners. Dark grey painted and superstructures, funnel and masts light brown.

Source

Bundesarchiv. German Marineattaché for , Greece, Romania and Bulgaria 1939-1941. RM 12-II/459.