During World War II, Japan built about nine thousand hydrogen-filled paper balloons to carry small bombs to North America in hopes of setting fires and causing casualties. The first was launched on November 3, 1944. Rising to about 30,000 feet, the balloons were carried across the Pacific Ocean by high-altitude winds. On February 22, 1945, Kenneth Hamilton, who lived on a nearby ranch, saw one floating eastward and said it looked like "an orange ball with the sun shining on it… As we were watching, it turned into a cloud of smoke and went to the ground." The balloons used timing devices to release their bombs and then destroy the envelope. Officials from Alliance Army Air Field recovered a valve and pieces of shroud lines where that balloon came down. Parts of five balloon bombs were recovered in Nebraska out of 285 reported incidents across North America. Though ineffective as military weapons, the balloon bombs caused six deaths and a few minor fires in the United States, and their story was revealed only after the war.