An undated handout image by The National Archives shows a page from a book issued to British secret service officials

An undated handout image released on September 3, 2006 by The National Archives shows a page from a book issued to British secret service officials. German spies hid secret messages in drawings of models wearing the latest fashions in an attempt to outwit Allied censors during World War Two, according to British security service files released on Monday. FOR EDITORIAL USE ONLY NO ARCHIVES NO SALES REUTERS/The National Archives/Handout