May 14, 1940, Mrs Steenbergh-Engeringh destroyed the archives in Holland “so that the invaders could not lay hands on them and use them to find people who had collaborated with us (the Union).” (Notebooks February 1946)

In June 1940, the German police searched the UILFC offices. Dr. J.H.E.J. Hoogveld, chaplain to IUCWL since 1930 was arrested by the Gestapo and died as a result of the ill-treatment he suffered. During this time work went on locally in some countries depending on their circumstances.