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)

A worker adds gunpowder into paper cylinders to make fireworks at a factory in Bocaue town, Bulacan province, Philippines, December 26, 2015. (Photo by Romeo Ranoco/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)

Supporters of the presidential candidate Muhammadu Buhari and his All Progressive Congress hits another supporter with a motorbike during celebrations in Kano, Nigeria March 31, 2015. (Photo by Goran Tomasevic/Reuters)

A fire engulfs The Address Hotel in downtown Dubai in the United Arab Emirates December 31, 2015. Fire engulfed a luxury building near the world’s tallest skyscraper in Dubai on Thursday as tens of thousands of people were gathering at its base for one of the world’s largest New Year’s fireworks displays. (Photo by Ahmed Jadallah/Reuters)

A Syrian youth Khaled from Raqqa walks on snow wearing slippers in the Bekaa Valley refugee camp in Lebanon after the first heavy snow storm hit Lebanon, January 3, 2016. (Photo by Jamal Saidi/Reuters)

A riot policeman fires into the air during clashes with opposition supporters at a rally demanding a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

A pilgrim walks on her knees to fulfil her vows, as pilgrims attend the 99th anniversary of the appearance of the Virgin Mary to three shepherd children, at the Catholic shrine of Fatima, Portugal May 12, 2016. (Photo by Rafael Marchante/Reuters)