A US Army M1A2 SEP tank participates in the Strong Europe Tank Challenge 2017 at the military training area in Grafenwoehr, Germany, 12 May 2017. Six North Atlantic Treaty Organization (NATO) nations and partner nations, Austria, France, Germany, Poland, Ukraine and the USA are taking part in this competing exercise. (Photo by Christian Bruna/EPA)

A participant in costume uses a mobile phone at a Halloween event in Kawasaki, south of Tokyo, Japan October 29, 2017. (Photo by Kim Kyung-Hoon/Reuters)

Aegean airlines air hostesses take selfies after a news conference in Athens, Wednesday, March 28, 2018. In a deal worth up to $5 billion, Greek airline Aegean says it will buy 30 new Airbus aircraft, with the option of an additional 12, to upgrade its fleet as the country expects to break tourism records. The signing of the final purchase agreement is expected in June. (Photo by Petros Giannakouris/AP Photo)

A participant poses for a photograph at the annual Easter Parade and Bonnet Festival in the Manhattan borough of New York City, New York, U.S. on April 1, 2018. (Photo by Gaia Squarci/Reuters)

An aerial view taken on September 11, 2020 shows the Buddhist temple Wat Samphran (Dragon Temple) in Nakhon Pathom, some 40km west of Bangkok. Wat Samphran is a popular tourist destination with visitors coming to see the huge dragon figure curling around a pink cylindrical building next to the Buddha statues and places of worship of the traditional Buddhist temple complex. (Photo by Mladen Antonov/AFP Photo)

Volunteers skin western diamondback rattlesnakes during the 2021 Rattlesnake Roundup at the Nolan County Coliseum in Sweetwater, Texas on March 13, 2021. The town of Sweetwater holds the largest rattlesnake roundup in the world, launched in 1958 with the sole purpose of getting rid of rattlesnakes, killing an average of 5,000 pounds of snake each year. (Photo by Paul Ratje/AFP Photo)

A Vietnamese woman, wearing the traditional “ao dai” long dress, poses for photos along peach blossom flowers ahead of the Vietnamese “Tet” (Lunar New Year festival), in a field in Hanoi, Vietnam, February 2, 2016. (Photo by Reuters/Kham)

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.