People run in panic after a coalition airstrike hit Islamic State fighters positions in Tahrir neighbourhood of Mosul, Iraq, November 17, 2016. (Photo by Goran Tomasevic/Reuters)

A person viewing the Northern lights over the lava landscape, Reykjanes Peninsula, Iceland. (Photo by Arctic-Images/Getty Images)

A member of security personnel stands on duty on an empty train platform inside a station on the Subway Line Number 1 on the eve of the Chinese Lunar New Year, in Beijing, China, February 7, 2016. According to local media, traffic in Beijing has seen a rare relief from its usual heavy pressure after 15 million people have left the city, heading for family reunions in their hometowns on the eve of the Chinese Lunar New Year of Monkey. (Photo by Jason Lee/Reuters)

Boys play with a drainage culvert used for flood control in Las Pinas, Metro Manila February 28, 2016. (Photo by Erik De Castro/Reuters)

An Egyptian passenger sits on the locomotive of a train as it leaves Cairo train station in Egypt, Wednesday, October 14, 2015. (Photo by Amr Nabil/AP Photo)

People take pictures and Buddhist monk chants as a groom and a bride lay inside a pink coffin during their wedding ceremony at Wat Takien temple in Nonthaburi province, on the outskirts of Bangkok February 14, 2015. Ten Thai couples laid in the pink coffin starting 9:09 AM on Saturday during the wedding ceremony organised by the Buddhist temple on Valentine's Day. Couples believe laying briefly in the coffin will get rid of bad luck and usher happiness into their lives. (Photo by Damir Sagolj/Reuters)

A priest blesses an elderly Romanian Roma couple after a religious service celebrating the Birth of the Virgin Mary at the Bistrita Monastery in Costesti, Romania, Monday, September 8, 2014. Thousands of Gypsies or Roma gather on a hillside after attending a religious service in a nearby monastery and celebrate the religious holiday by sharing food and playing traditional music until the next dawn. (Photo by Vadim Ghirda/AP Photo)

In this Sunday, May 29, 2016 photo, fighters take a selfie while firing artillery during fight against Islamic State militants in Fallujah, Iraq. Iraqi forces this week pushed into the city's southern sections after securing surrounding towns and villages more than 50,000 people are believed to be trapped inside the Sunni majority city, about 65 kilometers (40 miles) west of Baghdad. (Photo by Anmar Khalil/AP Photo)