Netherlands East Indies. (Singapore). 1940. Photographic post card of 'Durian seller' addressed to Morava bearing Netherlands Indies SG 403, 10c scarlet tied by Batavia date stamp '13th March 40', routed via Singapore with 'Passed For Transmission' hand-stamp and framed instructional 'Opened by British/ Naval Authorities' in violet on face and circular German censor cachet (+) applied on arrival in Munchen in red.
Scarce censor applied when Royal Navy ships boarded neutral (mostly Dutch) vessels and intercepted mail to Nazi Germany and Austria between Sept 39 and April 1940.
According to records just over 15 of these Navy censors are known