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)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

A health worker wearing a protective suit is disinfected inside a portable tent outisee the Gat Andres Bonifacio Memorial Medical Center during an enhanced community quarantine to prevent the spread of the new coronavirus in Manila, Philippines, Monday April 27, 2020. (Photo by Aaron Favila/AP Photo)

A member of a feminist group performs during a rally to celebrate International Women's Day in Santiago, Chile, March 8, 2021. (Photo by Ivan Alvarado/Reuters)

A French riot police officer is surrounded by flames, during a demonstration against the controversial labour reforms of the French government in Paris on September 15, 2016. Opponents of France's controversial labour reforms took to the streets on September 15, 2016 for the 14th time in six months in a last-ditch bid to quash the measures that lost the Socialist government crucial support on the left. Scores of flights in and out of France were cancelled as air traffic controllers went on strike to try to force the government to repeal the changes that became law in July. (Photo by Thomas Samson/AFP Photo)

Police intervene as two women fight at a pro-law enforcement rally that clashed with counter protesters demonstrating against racial inequality, in Denver, Colorado, U.S. July 19, 2020. (Photo by Kevin Mohatt/Reuters)

An artist wearing a coronavirus-shaped helmet and a protective suit stands next to a police barricade as he requests people to stay at home during an extended lockdown to slow the spread of the coronavirus disease (COVID-19) in New Delhi, India, April 30, 2020. (Photo by Adnan Abidi/Reuters)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)