Men work at Makala gold mine camp near the town of Mongbwalu in Ituri province, eastern Democratic Republic of Congo on April 7, 2018. (Photo by Goran Tomasevic/Reuters)

People dressed as characters from the computer game “World of Warcraft” walk across a field near the town of Kamyk nad Vltavou, Czech Republic, April 28, 2018. (Photo by David W. Cerny/Reuters)

A dog jumps into a swimming pool to retrieve a ball during the Chatsworth House Country Fair near Edensor, Britain on August 31, 2018. (Photo by Darren Staples/Reuters)

People gather on a hill near the Chopin Airport to watch aeroplanes taking off, in Warsaw, Poland, Sunday, September 9, 2018. (Photo by Alik Keplicz/AP Photo)

A USGS geologist making observations of the fissure 8 lava channel at sunset is pictured in this July 3, 2018 fisheye lens handout photograph near the Kilauea volcano eruption in Hawaii, U.S. (Photo by USGS/Handout via Reuters)

Sarah Bui poses for photographer, Brian Le around blossoming cherry trees, near the Tidal Basin on Thursday March 23, 2017 in Washington, DC. (Photo by Matt McClain/The Washington Post)

Iraqi paramilitary troops fire towards Islamic State militants during a battle with Islamic State militants on the outskirts of the ancient city of Hatra near Mosul,Iraq April 26, 2017. (Photo by Reuters/Stringer)

Internally displaced Syrian children who fled Raqqa city stand near their tent in Ras al-Ain province, Syria January 22, 2017. (Photo by Rodi Said/Reuters)