The newspapers reported rumors about Japanese Americans being spies. is your answer
Newspapers, in fear of an attack on the continental homeland, reported that there were sightings of fire balloons, Japanese ships, and Japanese airplanes over the West Coast, as well as Japanese-Americans called Nisei and Issei being spies. This led to the creation of a public defense force, as well as most Americans treating the Issei and Nisei's as spies and differently, leading to the US government responding and sending the Japanese-Americans to secluded camps.
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