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.

A Pasola rider reacts after throwing his spear during the Pasola war festival at Ratenggaro village on March 22, 2014 in Sumba Island, Indonesia. The Pasola Festival is an important annual event to welcome the new harvest season, which coincides with the arrival of “Nyale” sea worms during February or March each year. Pasola, an ancient ritual fighting game, involves two teams of men on horseback charging towards each other while trying to hit their rivals with “pasol” javelins and avoid being hit themselves. (Photo by Ulet Ifansasti/Getty Images)

A suspected street robber is arrested by a policeman after a brief chase in the streets, June 20, 2016, in Manila, Philippines. The president-elect of the Philippines, Rodrigo Duterte, declared a war on crime and drugs after sweeping an election on May 9 and has been living up to his nickname, “the punisher”. Philippine police have been conducting night raids almost on a daily basis and revived a curfew for minors that had not been enforced for years, rounding up minors drinking on the streets. (Photo by Dondi Tawatao/Getty Images)

Star Wars collector James Burns, 44, poses for a photograph with some of his collection in London December 2, 2015. He said “I've met so many wonderful people, all over the world. It's a wonderful community of likeminded people with an interest in Star Wars. There's nothing else like it”. (Photo by Paul Hackett/Reuters)

“Microscope images forge an extraordinary bond between science and art, said Hidenao Tsuchiya, Olympus America's Vice President and General Manager for the Scientific Equipment Group. We founded this competition to focus on the fascinating stories coming out of today's life science research laboratories. The thousands of images that people have shared with the competition over the years reflect some of the most exciting work going on in research today – work that can help shed light on the living universe and ultimately save lives. We look at BioScapes and these beautiful images as sources of education and inspiration to us and the world”. – OlympusBioScapes

Photo: Pretarsus of the third leg of a female drone fly (Eristalis tenax), ventral view, by Dr. Jan Michels, Institute of Zoology, Christian-Albrechts-University of Kiel, Germany. (Photo by Olympus BioScapes)

A performer is covered in chocolate sauce at the Notting Hill Carnival on August 28, 2011 in London, England. The annual carnival, which is the largest of it's kind in Europe and is expected to attract around 1 million revellers, has taken place every August Bank Holiday since 1966. (Photo by Oli Scarff/Getty Images)

Model Adriana Lima attends the 2011 Victoria's Secret Fashion Show After Party at Dream Downtown on November 9, 2011 in New York City. (Photo by Andy Kropa/Getty Images)

Clown/comedian/filmmaker Pierre Etaix attends The Academy Of Motion Picture Arts And Sciences' Presents “Pierre Etaix: The Laughter Returns” at AMPAS Samuel Goldwyn Theater on November 16, 2011 in Beverly Hills, California. (Photo by Valerie Macon/Getty Images)