The explosion was felt up to 37 miles away, more than three-quarters of Hiroshima's buildings were destroyed, and the shock wave itself is said to have shattered the windows of homes up to 10 miles away. Countless fires broke out due to the thermal pulse of the explosion which combined to start a firestorm that completely demolished everything within about 4 miles of where the bomb was dropped. Immediately after the bomb was dropped, a “black rain” began to fall in the northwestern part of the city, filled with soot, dust, dirt and radioactive material that had been raised into the air by the explosion. This black rain caused contamination in areas that were not even affected by the explosion, the bomb drop affected many more people than just the residents of Hiroshima. After seeing the explosion from an aerial view, the co-pilot of the B-29 bomber commented "My God, what have we done?", one can only imagine all the terrible thoughts that ran through that man's mind..