During the German invasion of Poland in September 1939, Ciężki escaped to France to continue work on Enigma ciphers, and in 1943 was captured by the Germans and interned in an SS concentration camp.
During the German invasion of Poland in September 1939, Ciężki escaped to France to continue work on breaking Enigma ciphers. In 1943 he was captured by the Germans and interned in an S.S. concentration camp.