Only after World War II did the secret spill: Ōkunoshima, located in the Inland Sea of Japan between Hiroshima and Shikoku, was the top-secret site for manufacturing chemical warfare. When the factories were closed down, a number of exotic wild rabbits were seen freely roaming the island. They were assumed to have been the test subjects for the chemical weapons, which the military failed to eradicate when the factory was demolished.

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A boy flies a handmade kite from a roof, following the outbreak of the coronavirus disease (COVID-19). in Old Cairo, Egypt on July 26, 2020. (Photo by Amr Abdallah Dalsh/Reuters)

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Hot air balloons in flight over Melbourne, Australia on January 24, 2022. (Photo by Rex Features/Shutterstock)