Alfons joined the resistance through contacts he made on the train. He set up resistance groups in Wingene and later also in Aartrijke. In August 1944, he was arrested and, after interrogation in Bruges and Ghent, deported to the Neuengamme concentration camp.
He barely survived the hardships: of the 195 men who were transported with him, only 10 returned. When he was liberated by the British, Alfons weighed barely 36 kg. On 25 June 1945, he returned to Wingene, where he received a warm welcome from the village community. He was recognised as a political prisoner.