A terrace of a house is covered with ash after the eruption of the Fuego volcano at San Miguel Los Lotes in Escuintla, Guatemala, June 6, 2018. (Photo by Carlos Jasso/Reuters)

A protester performs the symbolic death of a student demonstrator during a march near Congress where Chile's President Michelle Bachelet gives her annual address in Valparaiso, Chile, Thursday, May 21, 2015. Demonstrators are protesting the death of two students killed during an education reform march last week in Valparaiso and demanding more involvement in education reform. (Photo by Luis Hidalgo/AP Photo)

A thirty-year-old Dutch demonstrator displays a sign that reads: “Glad to be Gay” during a gay people march in Frankfurt, Germany on Saturday, July 28, 1979 which ended a week long homosexual meeting. Hundreds of homosexual converged for a week of movies, theater, rock concerts and workshops on gay rights. (Photo by Rolf Boehm/AP Photo)

Cheng Liping, whose husband Ju was onboard Malaysia Airlines Flight MH370 which disappeared on March 8, 2014, shows a picture of she and her husband together and an old card with a message given by her husband, at a park near her house where she and her husband used to visit during an interview with Reuters in Beijing July 24, 2014. Cheng said her life has been totally changed since the incident. Their two little sons, who don't know about this incident, keep asking her when their dad is coming back. Six months after Malaysia Airlines Flight MH370, with 239 mostly Chinese people on board, disappeared about an hour into a routine journey from Kuala Lumpur to Beijing March 8, loved ones of missing passengers derive what comfort they can from what's left behind after the world's greatest aviation mystery. More than two dozen countries have been involved in the air, sea and underwater search for the Boeing 777 but months of sorties failed to turn up any trace – even after narrowing the search area to the southern Indian Ocean – long after batteries on the black box voice and data recorders had gone flat. (Photo by Kim Kyung-Hoon/Reuters)

Masquerade performers participate in the annual Badagry cultural festival near the old slave port in Badagry, on the outskirts of Lagos, Nigeria August 27, 2016. (Photo by Akintunde Akinleye/Reuters)

An excavator removes a dead bear at the zoo in Tbilisi, Georgia, June 17, 2015. Tigers, lions, bears and wolves were among more than 30 animals that escaped from a Georgian zoo and onto the streets of the capital Tbilisi on Sunday during floods that killed at least 12 people. REUTERS/David Mdzinarishvili

A white Bengal tiger cub plays with its mother in a zoo in the Siberian city of Novosibirsk, about 2,800 kilometers (1,750 miles) east of Moscow, Russia, Tuesday, April 21, 2015. Two blue-eyed Bengal tiger cubs were born in March to a couple of white tigers at Novosibirsk zoo. (Photo by Ilnar Salakhiev/AP Photo)

A performer practices her mermaid swim next to a shark in an aquarium after graduating from a mermaid workshop in Guangzhou, Guangdong Province, China December 16, 2016. (Photo by Tyrone Siu/Reuters)