There was also one serious civilian race riot during the war; it occurred on June 20, 1943, in Detroit. A fist fight between a white man and a Negro sparked the resentment which had been mounting in that city. Thousands of Afro-Americans had been moving again from the South into the North to fill vacant jobs in war industry, and this was resented by local white residents. Before the Detroit riot ended, twenty-five Negroes and nine whites had been killed. President Roosevelt had to send in federal troops to quell the disturbance. Another factor which irritated Afro-Americans was that the Red Cross blood banks separated Negro and white blood. This was particularly humiliating in that it had been a Negro doctor, Charles Drew, who had done the basic research that made the banks possible. In spite of this, Afro-Americans were eager to demonstrate their patriotism and to support the war effort. Besides the hundreds of thousands who were involved directly in the military, millions more supported the war effort in countless other ways. Besides growing their own vegetables, saving tin cans and newspapers, they were avid contributors to the War Bond issues. Others volunteered to serve as block wardens in case of enemy air raids. Negro newspapers had their own journalists at the front, and the Afro-American community eagerly kept up with the war news. They took special pride in stories of heroism about Negro soldiers. When Hitler and his racist philosophy went down in defeat, they felt that they had achieved a personal victory and that at the same time they had made a contribution to America and the world. Thus, as the war came to a close and Afro-Americans looked forward to the postwar years with both apprehension and determination, they feared that, with the foreign antagonism eradicated, racist feeling at home might increase. At the same time, they were possessed by a new drive to make American democracy into a reality. The ideological character of the war had reminded them of America's expressed ideals of brotherhood and equality. Their participation in the war convinced them that they were worthy of full citizenship. Many had broken the bonds of tradition which had held them in fear and apathy. Some had left their communities to fight in the Army, and some had moved into large urban centers to work in defense industries. Although the war against racism abroad had ended, they were intent to see that the struggle for racial freedom and equality at home would continue. The U.S. and the U.N.