A rescue worker holds an injured boy after what activists said were airstrikes carried out by the Russian air force in Idlib city, Syria December 20, 2015. (Photo by Ammar Abdullah/Reuters)

Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

A man wearing a mask and dressed in a clown costume rides an electric tricycle while carrying a container in the shape of a rubber duck amid heavy smog in Beijing, China, December 29, 2015. (Photo by Jason Lee/Reuters)

A woman toes a tube carrying a man during the Ice and snow carnival at Taoranting park in Beijing, China, January 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)

A demonstrator is carried during a rally in support of a identity check draft law and against delinquency, in Santiago, Chile April 30, 2016. (Photo by Carlos Vera/Reuters)

Women carry a portable shrine, a Mikoshi, through a street in Tokyo's Asakusa district during the Sanja festival, Japan, May 15, 2016. (Photo by Thomas Peter/Reuters)

A man carries a woman across a river at Petit Goave where a bridge collapsed during the rains of the Hurricane Matthew, southwest of Port-au-Prince, October 5, 2016. (Photo by Hector Retamal/AFP Photo)

Voodoo believers carry dead goats during a ceremony of Fet Gede in a Peristil, a voodoo temple, in Port-au-Prince, Haiti, November 2, 2016. (Photo by Andres Martinez Casares/Reuters)