A “creuseur”, or digger, a plastic lantern on his head, readies to enter a copper and cobalt mine in Kawama, Democratic Republic of Congo on June 8, 2016. Cobalt is used in the batteries for electric cars and mobile phones. Working conditions are dangerous, often with no safety equipment or structural support for the tunnels. The diggers say they are paid on average US$2-3/day. (Photo by Michael Robinson Chavez/The Washington Post)

A Cuban migrant couple rests inside a tent at a provisional shelter in Paso Conoa, at the border with Costa Rica March 20, 2016. More than 1,500 Cuban immigrants are waiting at Costa Rica's southern border with Panama as they seek overland passage towards the United States, according to local officials. (Photo by Carlos Jasso/Reuters)

A man yells for help minutes after a Serb shell hit a crowded pedestrian walkway in Sarajevo, May 1993. Radovan Karadzic, a 70-year-old former psychiatrist, still in robust health, is the most senior political figure to be convicted by the International Criminal Tribunal for the Former Yugoslavia. He was found guilty of 10 out of 11 charges. He was acquitted of a second count of genocide in Bosnian towns. (Photo by Reuters)

Young girls carry containers filled with drinking water beside the railway station in Agartala, India, April 20, 2016. (Photo by Jayanta Dey/Reuters)

A boy holds a machine gun at a military hardware exhibition during a swear-in ceremony for new recruits of the Russian military-patriotic club “Yunarmia” (Young army) in the Black Sea port of Sevastopol, Crimea, October 27, 2018. (Photo by Pavel Rebrov/Reuters)

An unidentified elderly woman, who was knocked over during the melee after a shot was fired in the direction of President Ford, is comforted by a passerby in San Francisco, September 23, 1975. (Photo by AP Photo)

Kosovo- born British singer and actress Rita Ora performs in Pristina on February 17, 2018 on the occasion of the 10 th anniversary of Kosovo Independence. Kosovo celebrates 10 years since it declared independence, a moment of pride for its ethnic Albanian majority, although sovereignty remains fiercely contested by Serbia. (Photo by Armend Nimani/AFP Photo)

British troops covered in flames from a petrol bomb thrown during a violent protest by job seekers, who say they were promised employment in the security services, in the southern Iraq city of Basra, March 22, 2004. (Photo by Atef Hassan/Reuters)