A couple dance tango for tourists at Caminito, a touristic hotspot of La Boca neighborhood in Buenos Aires, Argentina, October 15, 2016. (Photo by Enrique Marcarian/Reuters)

A youth in make-up waits for the start of the annual Zombie walk in Mexico City, Saturday, October 22, 2016. Hundreds dressed in rags and ghoulish makeup to look bloody and decaying, gathered in the historic center of Mexico's capital. (Photo by Christian Palma/AP Photo)

A Christian worshipper reacts as she takes part in the Christian Orthodox Holy Fire ceremony at the Church of the Holy Sepulchre in Jerusalem's Old City, April 30, 2016. (Photo by Amir Cohen/Reuters)

Ukrainians pour water on each other on a street in Lviv, Ukraine, 02 May 2016. The tradition of pouring water was an ancient spring ritual of cleansing on first Monday after Orthodox Easter. (Photo by Mykola Tys/EPA)

A visitor holds an Israeli-made rifle during the 8th International Land and Naval Defense system exhibition, in New Delhi, India, on February 6, 2014. (Photo by Anindito Mukherjee/Reuters)

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.

A member of the mainly Christian “anti-balaka” (anti-machete) militia trains in the Boeing neighbourhood of Bangui, Central African Republic, on February 24, 2014. (Photo by Fred Dufour/AFP Photo)