Married to Trees (Theresa) Dahmen. In 1940 Charles was a reserve officer in the Dutch army and during the five day battle of the Netherlands he fought on the so called “Grebbenberg Line”, that the Dutch army held to the very end, repulsing heavy assaults from the German forces. After this, Charles Bongaerts was the head of the fire service in Heerlen, center of the coal mining area and this gave him access to vehicles which enabled him to play a prominent part in the underground resistance. They put up airmen in their home and transported them south on the long journey to England via Belgium, France and Gibraltar or Switzerland. On one occasion Charles Bongaerts stopped a German convoy and, claiming to be on urgent business, got a mechanic to repair his vehicle while three American airmen were in the back. 
Before the war, he used to be a journalist at the daily newspaper Limburgsch Dagblad in Heerlen. Together with some others, he founded the resistance newspaper Het Vrije Volk (The Free People), not to be confused with the same-named post-war newspaper. 
It was directed mainly at miners and was very well informed, because they had their people everywhere, even at the SiPo in Maastricht! [3.1]
Later, in addition to the escaped POWs, other refugees came in, such as Jews. As a result of infiltration into the Bongaerts group by Vastenhout (Englandspiel), Peeters, Reijnders and J.M.W. Clevis were arrested on November 16, 1943. Van Megen was shot dead in Dohnson, Germany, on April 5, 1945. Peeters died in Venlo on June 24, 1947. He had not recovered from the hardships of the Buchenwald camp. Clevis was released in May 1944, Reijnders only after the liberation. (in Dutch)
Sources: Traces of War  and Cammaert  and especially : Chapter IV §III. The Bongaerts group entangled in the Englandspiel: the Vastenhout affair.
He is buried in Ladelund. 
He is listed in the “Erelijst 1940-1945” (Honor Roll of the Dutch Parliament).