Because Vichy France was occupied by German troops in November 1942 , Vanderpoorten's freedom was strongly restricted. He was apprehended in January 1943, on suspicion of assistance to an escape line for refugees to the United Kingdom.
In November 1942, when Vichy France was under German control, Vanderpoorten's freedom was severely restricted. In January 1943, he was arrested on suspicion of helping a network that facilitated the escape of refugees to the United Kingdom.