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.

Fans dressed up in costume await the cast members on the red carpet at the world premiere of the film "The Avengers: Endgame" in Los Angeles, California, April 22, 2019. (Photo by Mario Anzuoni/Reuters)

People take part in a lowrider car show celebrating lowriding culture and supporting immigration, in San Francisco, California, U.S., September 20, 2025. (Photo by Manuel Orbegozo/Reuters)

Members of the US secret service scramble toward the stage as Donald Trump fell while speaking as shots rang out during a campaign rally at in Butler, Pennsylvania in 2024. (Photo by Jabin Botsford/Siena awards festival 2025)

Journalists practice social distancing outside a meeting to wrap up work on coronavirus economic aid legislation to prevent the spread of coronavirus disease (COVID-19) in Washington, U.S., March 21, 2020. (Photo by Mary F. Calvert/Reuters)

The social media star Demi Rose, 23, posed for a sizzling new photoshoot to promote her new swimwear line in Ibiza, Spain on Thursday, June 21, 2018. (Photo by KP Pictures)

Men from the Kenyan Maasai tribe perform a traditional jumping-ritual among fellow members of a common age-set as they observe a rite of passage to mark the transition of an age-set to cultural junior elder from Moran (Maasai for warrior age-set) at a manyatta or traditional homestead built specifically for the ceremony near Lemek town within the Masai-Mara National Reserve ecosystem in Narok county February 27, 2021. (Photo by Tony Karumba/AFP Photo)

The Doppler on Wheels (DOW) vehicle scans a supercell thunderstorm during a tornado research mission, May 8, 2017 in Elbert County near Agate, Colorado. Doppler on Wheels (DOW) is a mobile doppler radar mounted on a truck that brings instruments directly into storms, allowing scientists to scan storms and tornadoes and make 3-D maps of wind and debris. (Photo by Drew Angerer/Getty Images)