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)

In this file photo taken on Saturday May 1, 1993, an elderly communist woman clutches her head as police on horseback patrol the streets in Moscow. When Alexander Zemlianichenko started working as an AP photographer in Moscow, the Soviet Union was nearing its demise. (Photo by Alexander Zemlianichenko/AP Photo)

Indian policemen carry the body of one of their colleagues killed in a rebel attack in the town of Dinanagar, in the northern state of Punjab, India, Monday, July 27, 2015. Indian forces fought an extended gunbattle Monday with militants who attacked a moving bus and stormed into a police station in a northern town bordering Pakistan. (Photo by Channi Anand/AP Photo)

Two woman lie in a puddle of squashed tomatoes during the annual “Tomatina” tomato fight fiesta, in the village of Bunol, 50 kilometers outside Valencia, Spain, Wednesday, August 26, 2015. The streets of an eastern Spanish town are awash with red pulp as thousands of people pelt each other with tomatoes in the annual "Tomatina" battle that has become a major tourist attraction. At the annual fiesta in Bunol on Wednesday, trucks dumped 150 tons of ripe tomatoes for some 22,000 participants, many from abroad to throw during the hour-long morning festivities. (Photo by Alberto Saiz/AP Photo)

Thousands of travellers heading to their hometowns to celebrate Eid al-Fitr, the Muslim holiday to mark the end of Ramadan, wait in a traffic jam to board a ferry at the entrance to Gilimanuk port on Bali, Indonesia July 3, 2016 in this photo taken by Antara Foto. (Photo by Nyoman Budhiana/Reuters/Antara Foto)

In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

Revellers battle with tomato pulp during the annual “Tomatina” (tomato fight) festival in Bunol near Valencia, Spain, August 31, 2016. (Photo by Heino Kalis/Reuters)

In this August 1, 2014 photo provided by the National Park Service are male caribou antlers in the Oolah Valley, likely the result of a grizzly kill as he migrated south for the winter at the Arctic National Park and Preserve in Alaska. The nation's northernmost national park says its new management plan will have to consider the effects of a new industrial road to the mining district of Ambler, the first road that would be constructed within its Maryland-sized boundaries. (Photo by Cadence Cook/AP Photo/National Park Service)