An army tank fires during a firefight against militants linked to al Qaeda near the southern Yemeni city of Zinjibar May 30, 2012. (Photo by Reuters/Yemen's Defence Ministry)

Bikers push their motorbikes during a traffic block as they take part in the “Enduropale” motorcycle endurance race on the beach of Le Touquet, northern France, February 1, 2015. About 1100 motorbike and 600 quad bike riders descend on Le Touquet every year for the racing endurance event. (Photo by Pascal Rossignol/Reuters)

This picture taken on February 1, 2015 shows participants competing in a tofu (beancurd) wrestling competition in Fogang county, south China's Guangdong province. Participants, mostly women, fight it out in an inflatable pool which is filled with nearly two tons of fresh milk and tofu, in a promotion to attract tourists for the upcoming Chinese Lunar New Year holiday. The upcoming Chinese lunar new year of the sheep, which will fall on February 19 this year, marks the biggest festival of the year in China as hundreds of millions of people journey across the country to celebrate the season with their families. (Photo by AFP Photo/Stringer)

An Afghan journalist takes a “selfie” as U.S. President Barack Obama (R) holds a joint news conference with Afghanistan's President Ashraf Ghani (C) at the White House in Washington March 24, 2015. (Photo by Jonathan Ernst/Reuters)

A girl marches alongside Salvadoran soldiers during the parade commemorating Independence Day in San Salvador, El Salvador September 15, 2016. (Photo by Jose Cabezas/Reuters)

Hamar women dance before a bull jumping ceremony in Ethiopia's southern Omo Valley region near Turmi on September 19, 2016. The Hamar are a Nilotic ethnic group in Ethiopia. The construction of the Gibe III dam, the third largest hydroelectric plant in Africa, and large areas of very “thirsty” cotton and sugar plantations and factories along the Omo river are impacting heavily on the lives of tribes living in the Omo Valley who depend on the river for their survival and way of life. (Photo by Carl De Souza/AFP Photo)

Girls hold hands as they help each other wade through a flooded street after the passing of Hurricane Matthew in Les Cayes, Haiti, Thursday, October 6, 2016. Two days after the storm rampaged across the country's remote southwestern peninsula, authorities and aid workers still lack a clear picture of what they fear is the country's biggest disaster in years. (Photo by Dieu Nalio Chery/AP Photo)