A man fires a weapon as he dances during a traditional excursion near the western Saudi city of Taif, August 8, 2015. Saudis usually party in such excursions as they celebrate weddings or graduations. (Photo by Mohamed Al Hwaity/Reuters)

A Zimbabwean subsistence farmer holds a stunted maize cob in his field outside Harare, January 20, 2016. About 14 million people face hunger in Southern Africa because of a drought that has been exacerbated by an El Nino weather pattern, the United Nations World Food Programme (WFP) said on Monday. In Zimbabwe, 1.5 million people, more than 10 percent of the population, face hunger, WFP said. (Photo by Philimon Bulawayo/Reuters)

Participants hang from ropes as they learn how to use safety gears at an experience centre for construction safety training in Beijing, September 5, 2014. The centre which opened in June 2014 was established to educate workers about construction safety. According to the centre, about 1,000 construction workers undergo 3-hour classes which comprises of 33 modules every month. (Photo by Kim Kyung-Hoon/Reuters)

Dhruva Aliman does a back somersault as he dismounts from a slackline on the beach at Santa Monica, California on October 19, 2014. Slackline is a balance sport where a line of webbing is adjusted at different levels of tension between two anchor points and participants (called slackers) perform tricks and stunts including somersaults. (Photo by Mark Ralston/AFP Photo)

Russia's Maria Stavitskaia performs during the ladies short program at the Rostelecom Cup ISU Grand Prix of Figure Skating in Moscow November 14, 2014. (Photo by Grigory Dukor/Reuters)

Rebel fighters fire towards positions of regime forces in Ramussa on the southwestern edges of Syria's northern city of Aleppo on August 6, 2016. Syrian rebels said they have broken a three-week government siege of second city Aleppo, turning the tables on Russian-backed regime forces who are now on the defensive. (Photo by Fadi Al-Halabi/AFP Photo)

An airplane is silhouetted at sunrise, seen from the suburb of Saint-Cloud, near Paris, France, 08 December 2016. Paris is undergoing a third day pollution spike, prompting the city to limit vehicle circulation. (Photo by Ian Langsdon/EPA)

Rohingya refugee children pictured in a camp in Cox's Bazar, Bangladesh, September 19, 2017. With a mass exodus of Rohingya Muslims sparking accusations of ethnic cleansing from the United Nations and others, Myanmar leader Aung San Suu Kyi on Tuesday said her country does not fear international scrutiny and invited diplomats to see some areas for themselves. (Photo by Cathal McNaughton/Reuters)