In this photo provided by World Press Photo, the 1st Prize Daily Life Single of the 2011 World Press Photo Contest by Omar Feisal, Somalia, Reuters, shows a man carrying a shark through the streets of Mogadishu, Somalia, September 23, 2010. (AP Photo/Omar Feisal/Reuters)

Schoolchildren look at a lifelike animatronics display of a dinosaur at the dinosaur-themed Zoo-rassic Park in Singapore on November 16, 2016. To raise awareness on the sixth mass extinction, the Singapore Zoo and River Safari displayed lifelike dinosaur animatronics where visitors can trail along the Dinosaur Valley which does not involve living animals. (Photo by Roslan Rahman/AFP Photo)

An Indian Hindu widow smeared with colors sits and watches others playing during Holi celebrations at the Gopinath temple, 180 kilometres (112 miles) south-east of New Delhi, India Monday, March 21, 2016. A few years ago this joyful celebration was forbidden for Hindu widows. Like hundreds of thousands of observant Hindu women they would have been expected to live out their days in quiet worship, dressed only in white, their very presence being considered inauspicious for all religious festivities. (Photo by Manish Swarup/AP Photo)

An alpaca is seen near the Inca citadel of Machu Picchu in Cusco December 2, 2014. Machu Picchu, a UNESCO World Heritage Site, is Peru's top tourist attraction, with the government limiting tourists to 2,500 per day due to safety reasons and concerns over the preservation of the ruins. (Photo by Enrique Castro-Mendivil/Reuters)

Indian artist Sudarsan Pattnaik works on a sand sculpture depicting drowned Syrian boy Aylan Kurdi at Puri beach, some 65 kilometers away from Bhubaneswar, on September 4, 2015. Charities helping refugees saw a surge in donations on September 4 across Europe as people shocked by the heart-rending images of a drowned Syrian boy on a Turkish beach dug deep to help out. The photos of the lifeless body of three-year-old Aylan Kurdi, lying on a beach in Bodrum, Turkey, have triggered a wave of emotion across the continent, despite deep divisions among European governments on how to deal with the crisis. (Photo by Asit Kumar/AFP Photo)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)

Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.

Howard Jackson, a Liberian migrant, poses for a portrait in the Andalusian capital of Seville, southern Spain March 7, 2016. Jackson escaped civil war and spent three years crossing Africa before reaching Spain. Dressed up in one of his more than 200 costumes, from Peter Pan to Little Red Riding Hood, he is a well-known figure at an intersection entering the Spanish city of Seville where he has sold tissues to motorists for over a decade. Jackson is studying law and wants to become a judge. (Photo by Marcelo del Pozo/Reuters)