The naval defence of Tanger, Marocco according to the Kriegsnachrichten of the Chef des Admiralstabes der Marine dated Berlin 9 August 1917

An item reported that according to the naval attache at Madrid on 4 August in Tanger, Morocco were stationed 4 guard vessels and British motor boats fitted out with radio telegraphy systems. At sea were British torpedo boats and steam fishing vessels. With good weather went the motor boats as far as Larache but always returning in the evening to Tanger.

Source

Bundesarchiv RM-40-622