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.

Patarawan fixes her boots as her parrot, Sim sits on her head as she goes shopping for dinner at a busy flooded market near the Chao Phraya river October 27, 2011 in Bangkok, Thailand. Hundreds of factories closed in the central Thai province of Ayutthaya and Nonthaburi as the flood waters began to reach Bangkok. Around 350 people have died in flood-related incidents since late July according to the Department of Disaster Prevention and Mitigation, with Thailand experiencing the worst flooding in 50 years. (Photo by Paula Bronstein/Getty Images)

In this Thursday, August 11, 2016, photo, the injured are helped after a bomb blast in the southern resort city of Hua Hin, 240 kilometers (150 miles) south of Bangkok, Thailand. Police are investigating a series of bomb blasts in Hua Hin and other cities in Thailand. (Photo by Daily News via AP Photo)

Recruits carry ammunition during a military training at a firing range in the Rostov-on-Don region in southern Russia, on October 4, 2022. Russian Defense Minister Sergei Shoigu said that the military has recruited over 200,000 reservists as part of a partial mobilization launched two weeks ago. (Photo by AP Photo/Stringer)

A couple buy a sugar-coated Chinese haw to a child at the Qianmen pedestrian shopping street, a popular tourist spot in Beijing, Tuesday, January 3, 2023. (Photo by Andy Wong/AP Photo)

Belgium's Crown Princess Elisabeth, center, marches past the Royal tribune with cadets of the military school during the National Day parade in Brussels, Wednesday, July 21, 2021. Belgium celebrates its National Day on Wednesday in a scaled down version due to coronavirus, COVID-19 measures. (Photo by Olivier Matthys/AP Photo)

A girl takes a skateboard class from the NGO “CDD Skate Arte”, at a public skate park in the City of God favela of Rio de Janeiro, Brazil, Thursday, August 5, 2021. (Photo by Bruna Prado/AP Photo)

Participants jump into the water during the 114th edition of the Copa Nadal (Christmas Cup) swimming race in Barcelona's Port Vell on December 25, 2023. The traditional 200-meter Christmas swimming race gathered around 300 participants on Barcelona's Port Vell (old harbour). (Photo by Josep Lago/AFP Photo)