The German military took over Będzin on the first day of the invasion, burned the Grand Synagogue down within a week, and began massive resettlement actions. On October 28, 1940 Gertner was ordered to report to the train station in nearby Sosnowiec, where she was taken to a Nazi labor camp in Geppersdorf (now Rzedziwojowice), a construction site where hundreds of Jewish men were used as forced laborers on the "Reichsautobahn" section (now Berlinka) and where women worked in the kitchen and laundry. Gertner, who was fluent in German, was assigned to the camp office, where she met prisoner Bernhard Holtz whom she would marry in the Będzin Ghetto in the following year.