By the end of the war, a significant percentage of aircraft production originated in concentration camps, an industry employing tens of thousands of prisoners.[N 3] The Luftwaffe's demand for labor was one of the factors that led to the deportation and murder of hundreds of thousands of Hungarian Jews in 1944. The Oberkommando der Luftwaffe organized Nazi human experimentation, and Luftwaffe ground troops committed massacres in Italy, Greece, and Poland.