Migrants climb through the windows of a train bound for Serbia at the train station in Gevgelija, The Former Yugoslav Republic of Macedonia, 19 July 2015. Thousands of migrants who crossed Greece are on their way through Macedonia towards Serbia in order to access other European countries. Hungary in mid-July started to put up a fence on its border with Serbia, which makes the situation with the migrants in the transit countries even more complicated. The European countries on 20 July will discuss the quota of how many migrants each country should accept. (Photo by Georgi Licovski/EPA)

A huge supercell dominates the Texas skyline like an atomic bomb explosion on April 11, 2015 in Lubbock, Texas. A huge supercell dominates the Texas skyline like an atomic bomb explosion. These incredible images were taken on April 11th, by photographer Darin Kuntz who has spent in his entire life in so-called Tornado Alley. And Darin confirmed that he snapped the storm standing in his backyard in Lubbock, Texas. (Photo by Darin Kuntz/Barcroft Media)

North Koreans who signed up to join the army train in the midst of political tension with South Korea, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang August 23, 2015. Top aides to the leaders of North and South Korea resumed talks on Sunday after negotiating through the night in a bid to ease tensions involving an exchange of artillery fire that brought the peninsula to the brink of armed conflict. (Photo by Reuters/KCNA)

A rebel fighter supporter shoots an AK-47 rifle as she reacts to the news of the withdrawal of Libyan leader Muammar Gaddafi's forces from Benghazi March 19, 2011. The conflict was sparked by clashes in Benghazi and escalated into a rebellion that spread across the country. Gaddafi was captured and killed on October 20, 2011. Libya is currently caught up in a conflict between two rival factions who once battled together against the late Libyan leader. (Photo by Goran Tomasevic/Reuters)

Two pins featuring former North Korean leader Kim Il Sung wearing different facial expressions are displayed in a glass case of Thomas Hui at his apartment in Hong Kong, China April 11, 2016. Collector Thomas Hui, 37, a former bank employee in Hong Kong, who is fascinated by North Korean pins and badges, has gathered over 100 featuring former leaders Kim Il Sung and Kim Jong Il, and has been buying and trading these Communist accessories since 2008. (Photo by Bobby Yip/Reuters)

A Syrian boy is comforted as he cries next to the body of a relative who died in a reported airstrike on April 27, 2016 in the rebel-held neighbourhood of al-Soukour in the northern city of Aleppo. The Syrian army was preparing an offensive to retake the whole of Aleppo, as fighting in the divided second city killed 38 civilians in a new blow for a tattered truce. Nearly 200 people have been killed in Aleppo in the past week as rebels have pounded government-held neighbourhoods with rocket and artillery fire and the regime has hit rebel areas with air raids. (Photo by Karam Al-Masri/AFP Photo)

A woman crowd-surfs in front of the main stage at the Woodstock Festival in Kostrzyn-upon-Odra, close to the Polish-German border, August 2, 2014. Some 500 thousand people attended the festival that is the brainchild of Polish journalist and social campaigner Jerzy Owsiak. He initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Thomas Peter/Reuters)

A group of daredevil divers get perilously close to a school of deadly sharks – and one even lies on his back with his arm folded. The relaxed diver swims on his back and almost hugs the shark who is floating directly above him. The freedivers – Carlos Estrabeau, 28, and 29-year-old Ocean Ramsey – are friends with photographer Raul Boesel Jr. Photographer Raul Boesel Jr from Curitiba, Brazil, travelled to West End in the Bahamas to capture images of the giant sharks. (Photo by Raul Boesel/Solent News & Photo Agency)