The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. The Chernobyl disaster is the worst nuclear power plant accident in history in terms of cost and resulting deaths, and is one of only two classified as a level 7 event (the maximum classification) on the International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster in 2011). Photo: Graffiti of a crying baby on a wall, Chernobyl Power Plant, Chernobyl, Ukraine. (Photo by Hans Neleman/Getty Images)

North Korean women in colorful traditional dresses are surrounded by flower blossoms known as “Kimilsungia” as they wait to guide guests at a flower exhibition in Pyongyang, North Korea, April 14, 2014. The flowers, named after Kim Il Sung, are on display to celebrate the late leader's official birth date of April 15, 1912. (Photo by David Guttenfelder/AP Photo)

Iraqi army soldiers attempt to move their truck stuck in the mud near the village of Al-Boutha al-Sharqiyah, west of Mosul, on December 2, 2016, during a broad offencive by Iraq forces to retake the main hub city from Islamic State group jihadists. (Photo by Ahmad Al-Rubaye/AFP Photo)

Belarusians wearing national costumes celebrate a Pull the Kolyada Up the Oak rite in the village of Martsiyanauka, some 77 km (48 miles) east of capital Minsk, Belarus, Thursday, January 21, 2016. The merry ancient rite Pull the Kolyada Up the Oak marks the end of Orthodox Christmas celebrations in Belarus. On Jan. 21 a wheel, the so-called Kolyada, would be pulled up an oak or any old tree. The Belarusians believed that the ritual heralds a good harvest, luck and happiness for the entire year. (Photo by Sergei Grits/AP Photo)

Scottish Fold cat is displayed during a cat exhibition in Bishkek, Kyrgyzstan, 26 November 2017. Cats owners from Kyrgyzstan and Kazakhstan gathered in Bishkek to show their pets. (Photo by Igor Kovalenko/EPA/EFE/Rex Features/Shutterstock)

A devotee offers prayers to the setting sun during the "Chhat" festival at Bagmati river in Kathmandu, Nepal November 17, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god, by praying at sunrise and sunset, and seek blessings for one's family by giving offerings. (Photo by Navesh Chitrakar/Reuters)

Vendors sell their wares at a parking garage for commercial transports in Obalende district in Nigeria's commercial capital Lagos November 23, 2015. (Photo by Akintunde Akinleye/Reuters)

A Cambodian tuk tuk driver and guide with a tarantula in his mouth shortly after is was dug from the ground on June 7, 2010 in Skuon, Kampong Cham Province, Cambodia. The trade for spiders and other insects as food and for medicinal purposes has been in effect since the 1970's in Cambodia but only very recently have tourists been finding a way to see where the spiders are hunted in the nearby countryside. One guide, who can be found in Kampong Cham Town has started offering tours to tourists who can find him. (Photo by Tim Whitby/Getty Images)