<P> The Tokyo control operator of the Japan Broadcasting Corporation noticed that the Hiroshima station had gone off the air . He tried to re-establish his program by using another telephone line, but it too had failed . About 20 minutes later the Tokyo railroad telegraph center realized that the main line telegraph had stopped working just north of Hiroshima . From some small railway stops within 16 km (10 mi) of the city came unofficial and confused reports of a terrible explosion in Hiroshima . All these reports were transmitted to the headquarters of the Imperial Japanese Army General Staff . </P> <P> Military bases repeatedly tried to call the Army Control Station in Hiroshima . The complete silence from that city puzzled the General Staff; they knew that no large enemy raid had occurred and that no sizable store of explosives was in Hiroshima at that time . A young officer was instructed to fly immediately to Hiroshima, to land, survey the damage, and return to Tokyo with reliable information for the staff . It was felt that nothing serious had taken place and that the explosion was just a rumor . </P> <P> The staff officer went to the airport and took off for the southwest . After flying for about three hours, while still nearly 160 km (100 mi) from Hiroshima, he and his pilot saw a great cloud of smoke from the bomb . After circling the city in order to survey the damage they landed south of the city, where the staff officer, after reporting to Tokyo, began to organize relief measures . Tokyo's first indication that the city had been destroyed by a new type of bomb came from President Truman's announcement of the strike, sixteen hours later . </P> <Table> <Tr> <Td> </Td> <Td> Truman announcing the bombing of Hiroshima President Truman announces the bombing of Hiroshima, which he describes as "a military base". </Td> </Tr> <Tr> <Td_colspan="2"> Problems playing this file? See media help . </Td> </Tr> </Table>

Who was the us president when hiroshima was bombed