A protesting student runs past a burning bus off campus outside the University of the Witwatersrand in Johannesburg, South Africa on Monday, October 10, 2016. Tear gas and water cannon were fired as hundreds of students protested at the university amid a bitter national dispute with university managers and the government over demonstrators' demands for free education, forcing student into the neighbouring city streets. (Photo by AP Photo)

A man takes a selfie in front of a fire from oil that has been set ablaze in the Qayyarah area, some 60 kilometres (35 miles) south of Mosul, on October 19, 2016, during an operation by Iraqi forces against Islamic State (IS) group jihadists to retake the main hub city. In the biggest Iraqi military operation in years, forces have retaken dozens of villages, mostly south and east of Mosul, and are planning multiple assaults for October 20. (Photo by Yasin Akgul/AFP Photo)

A Shiite fighter from the Hashed al-Shaabi (Popular Mobilisation) patrols in the village of Ayn Nasir, south of Mosul, on October 29, 2016, after recapturing it from Islamic State group jihadists in an ongoing operation to retake the city of Mosul. Iraqi paramilitary forces launched an operation to cut the Islamic State group's supply lines between its Mosul bastion and neighbouring Syria, opening a new front in the nearly two-week-old offensive. (Photo by Ahmad Al-Rubaye/AFP Photo)

Skeletons are arranged in a bar scene as part of a competition to create Day of the Dead altars on pedestrian Regina Street in central Mexico City, Tuesday, November 1, 2016. The holiday honors the dead as friends and families gather in cemeteries to decorate their loved ones' graves and hold vigil through the night on Nov. 1 and 2. (Photo by Rebecca Blackwell/AP Photo)

Fighters of the Free Syrian Army fire an anti-aircraft weapon in the rebel-held Mashhad area in southeastern Aleppo, on December 12, 2016, as they battle Syrian government forces during an operation to retake the embattled city. The crucial battle for Aleppo entered its “final phase” after Syrian rebels retreated into a small pocket of their former bastion in the face of new army advances. The retreat leaves opposition fighters confined to just a handful of neighbourhoods in southeast Aleppo, the largest of them Sukkari and Mashhad. (Photo by AFP Photo/Stringer)

Fireworks explode over the Kremlin in Red Square which was blocked by police during New Year celebrations in Moscow, Russia, Sunday, January 1, 2017. New Year's Eve is Russia's major gift-giving holiday, and big Russian cities were awash in festive lights and decorations. (Photo by Alexander Zemlianichenko Jr./AP Photo)

Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

An Orangutan named “Pacquiao” and zoo owner Manny Tangco, wearing Santa costumes, embrace in front of Brown Philippine Deer while giving school children a tour ahead of the next week's Christmas celebration Thursday, December 18, 2014 in suburban Malabon city, north of Manila, Philippines. The yearly treat is aimed at encouraging residents to be sensitive to the feelings of animals especially when exploding firecrackers for the raucous celebration. (Photo by Bullit Marquez/AP Photo)