Chief priest Gbenga Saala raises a cutlass to kill a dog during an annual prayer and sacrifice celebration of the iron god Ogun in Abuja, Nigeria, June 23, 2015. Every year worshippers offer a dog as sacrifice to Ogun, a traditional Nigerian deity, in hope of an auspicious year ahead. Taxi drivers, blacksmiths, panel beaters and mechanics – trades that depend on metal for their livelihood – pay homage to Ogun, led by high priest Gbenga Saala. As part of the ceremony, the priest pours the dog’s blood on symbols of these workers’ trade: keys, spanners and other tools piled up in a metal barrel. (Photo by Afolabi Sotunde/Reuters)

A man runs after he tried to put himself on fire during a protest at a makeshift camp at the Greek-Macedonian border near the village of Idomeni on March 22, 2016. Greece will not be able to start sending refugees back to Turkey from March 20, 2016, the government said, as the country struggles to implement a key deal aimed at easing Europe's migrant crisis. The numbers are daunting: officials said as of Saturday there were 47,500 migrants in Greece, including 8,200 on the islands and 10,500 massed at the Idomeni camp on the Macedonian border. (Photo by Andrej Isakovic/AFP Photo)

Rahma, 19 (L), pictured with her 10-year old brother Fahad on June 21, 2016 in Kano, Nigeria. A teenage girl born without limbs lives her life in a plastic bowl. Rahma Haruna is a bright, happy girl, despite suffering from a mystery condition that stopped her arms and legs developing properly – leaving her practically limbless and in constant pain. The 19-year- old, from Kano, Nigeria, was born a healthy baby but when she turned six months old her growth came to a sudden halt and she stopped hitting key development milestones. Rahma’s family do their best to provide her with a fulfilling life and transport her around the village in a plastic bowl. Rahma said: “They help me a lot. How do they? They give me anything I need”. Rahma died on 25 December 2016. (Photo by Sani Maikatanga/Barcroft Images)

A French soldier stands near a military combat command vehicle on display at The Defence and Security Exhibition on September 13, 2011 in London, England. ExCeL London is hosting the exhibition with hundreds of manufacturers from all over the world displaying their hardware. (Photo by Peter Macdiarmid/Getty Images)

Paintings are moved on a stand at the “London Art Fair” on January 18, 2012 in London, England. The fair includes over 100 different stands featuring work by well known 20th century British artists and showcases some of the best emerging talent in the art world today. The show runs until January 23, at Business Design Centre in Islington. (Photo by Dan Kitwood/Getty Images)

A pheasant stands in snow near Dulverton on January 30, 2012 on Exmoor, England. After unseasonably mild winter weather, some parts of the UK woke to a covering of snow as a cold spell of weather sets in, with forecasters warning temperatures are set to plunge as the week progresses. (Photo by Matt Cardy/Getty Images)

Soldiers stand in line outside portable toilets during a military parade to celebrate the 206th anniversary of Colombia's independence in Bogota, Colombia, July 20, 2016. (Photo by John Vizcaino/Reuters)

A man stands near bodies of his young relatives after an airstrike in the rebel held Douma neighbourhood of Damascus, Syria August 22, 2016. (Photo by Bassam Khabieh/Reuters)