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.

Sjinkie Knegt of Netherlands, left, and Park Se-Yeong of South Korea crash out as they compete in a men's 1500m short track speedskating final at the Iceberg Skating Palace during the 2014 Winter Olympics, Monday, February 10, 2014, in Sochi, Russia. (Photo by Bernat Armangue/AP Photo)

Fans of Chris Mazdzer of the United States including his girlfriend Mara Marian (C) react following his third run during the Luge Men's Singles on day two of the PyeongChang 2018 Winter Olympic Games at Olympic Sliding Centre on February 11, 2018 in Pyeongchang-gun, South Korea. (Photo by Alexander Hassenstein/Getty Images)

Serge Huguenin of the Blondeau foundry takes the newly melted bell out of the mould in La Chaux-de-Fonds, Switzerland January 21, 2016. At this year's Summer Olympics in Rio de Janeiro, no matter how elaborate the opening ceremony or how sophisticated the live broadcasts, the final lap of athletics races will be announced the traditional way by ringing an old-fashioned bell. Omega, the official timekeeper of the event, has ordered 21 bells, forged almost entirely by hand by Blondeau's Bell Foundry in the Jura Mountains in Switzerland. Each last-lap bell is branded with the RIO 2016 logo and circled with the words “2016 GAMES OF THE XXXI OLYMPIAD”. (Photo by Denis Balibouse/Reuters)

Members of a samba school warm up before parading along Copacabana Beach in Rio de Janeiro, Brazil, Saturday, January 6, 2018. Musicians and members from Rio de Janeiro's top 13 samba schools have paraded in an event aimed at promoting tourism ahead of Rio's world famous Carnival that begins early next month. (Photo by Leo Correa/AP Photo)

A policeman is pictured near a woman with a baby during an operation against drug dealers in Cidade de Deus or City of God slum in Rio de Janeiro, Brazil, November 23, 2016. (Photo by Ricardo Moraes/Reuters)

Breitling Wingwalker Freya Paterson, from Liverpool, UK, flies above Kuwait City's iconic Water Towers with pilots David Barrell and Martyn Carrington, on March 6, 2014. The team loop and roll up to 160 mph enduring G-forces of 4-5g. Crowds are expected to line the Kuwaiti coastline to catch a glimpse of the Wingwalking team on Saturday, March 8, 2014, to mark the opening of the first dedicated boutique in the city for the prestigious watch brand. (Photo by Katsuhiko Tokunaga/Breitling)