The Japanese sent 9,300 balloon bombs floating across the Pacific Ocean during World War II. Though probably fewer than 1,000 balloons made it all the way across the Pacific, several did cause damage when they exploded into fiery balls in places like Montana, Wyoming, Colorado, North and South Dakota, and Canada. Called FU-GO by the Japanese, the balloons carried bombs that were mostly intended to start forest fires. In general, the incidents were not reported in newspapers, because the United States didn’t want Japan to know whether their plan had been successful.(emphasis mine)
What an interesting time that must have been, when the newspapers and/or government officials knew how to keep their pie holes shut when it counted.