Simon de la Bella, vice-chairman of the Nederlands Verbond van Vakverenigingen (NVV) was arrested on 20 July 1940. He had managed to transfer five million guilder of NVV's finances to England in time. During his arrest, he tried to commit suicide by taking poison, but the attempt failed. He was killed in Dachau on 10 July 1942, at the age of 52.
NIOD, Erelijst Verzet en Koopvaardij, database made by J.W. de Leeuw
For additional information see:
J. Presser, Ondergang. De vervolging en verdelging van het Nederlandse jodendom 1940-1945. Deel I (Den Haag 1965) 24-25.
See also his biography in Biografisch Woordenboek van het Socialisme en de Arbeidersbeweging in Nederland [in Dutch].
In addition, a Jokos file (number 3863) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.