A demonstrator kicks a riot police vehicle during an unauthorized march called by the Chilean student federations to protest against government's education reform, in Santiago, Chile July 5, 2016. (Photo by Ivan Alvarado/Reuters)

Libyan forces allied with the U.N.-backed government fire weapons during a battle with IS fighters in Sirte, Libya, July 21, 2016. (Photo by Goran Tomasevic/Reuters)

Kurdish pesh merga troops fire at Islamic State positions as they move toward the Iraqi town of Badana Pichwk on Monday morning, October 17, 2016. Kurdish forces began Monday advancing on a string of villages east of Mosul, the start of a long-awaited campaign to reclaim Iraq's second-largest city from the Islamic State, which seized it more than two years ago, officials said. (Photo by Bryan Denton/The New York Times)

Renaud Lavillenie of France in action while competing in the Mens Pole Vault during the Air Show “Berlin fliegt!” at Brandenburger Tor on August 12, 2011 in Berlin, Germany. (Photo by Joern Pollex/Bongarts/Getty Images)

Turkish Kurds watch the Syrian town of Kobani from near the Mursitpinar border crossing, on the Turkish-Syrian border in the southeastern town of Suruc, October 19, 2014. (Photo by Kai Pfaffenbach/Reuters)

Iraqi pro-government forces fire an anti-tank cannon near al-Sejar village, north-east of Fallujah, on May 25, 2016, as they take part in a major assault to retake the city from the Islamic State (IS) group. Iraqi forces, consisting of special forces, soldiers, police, paramilitary-fighters and pro-government tribesmen, launched a major assault to retake Fallujah, the scene of deadly battles during the US occupation and one of the toughest targets yet in Baghdad's war on the Islamic State group. (Photo by Ahmad Al-Rubaye/AFP Photo)

Young African lion Asali (R) jumps for a bungee-ball toy as her father Jambo or “Bruiser” looks on at the opening of a savannah-themed makeover of the lion enclosure at Taronga Zoo August 29, 2006 in Sydney, Australia. The renovation includes sandstone rock features, a wading pool, and red ochre crushed granite substrate in a move to make the enclosure more closely resemble the natural habitat of the African savannah. (Photo by Ian Waldie/Getty Images)

A videographer uses a drone as he takes a video of a model presenting a lingerie creation at the rehearsal for Eve's Temptation collection during China Fashion Week in Beijing, October 26, 2014. (Photo by Kim Kyung-Hoon/Reuters)