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 Colombian anti-narcotics policeman stands guard after burning a cocaine lab, which police said belongs to criminal gangs, in a rural area of Calamar in Guaviare state, Colombia, August 2, 2016. Colombian law enforcement has destroyed 104 cocaine laboratories capable of producing some 100 tonnes of the drug annually, the head of the anti-narcotics police said on Tuesday. (Photo by John Vizcaino/Reuters)

Edibles are displayed at Shango Cannabis shop on first day of legal recreational marijuana sales beginning at midnight in Portland, Oregon October 1, 2015. The sale of marijuana for recreational use began in Oregon on October 1, 2015 as it joined Washington state and Colorado in allowing the sale of a drug that remains illegal under U.S. federal law. (Photo by Steve Dipaola/Reuters)

Nelson Mandela make up complete. 40-year-old London-based makeup artist, Maria Malone-Guerbaa has the ability to transform herself into any celebrity or creature using only her basic makeup essentials. Maria used only make up and face paints to create the illusion of Nelson Mandela, Britain's Queen Elizabeth II, and many other A-list celebrities. (Photo by Maria Malone-Guerbaa/Rex Features USA)

Police officers stand near a fishing boat, the Carolina Queen III, as it rests in shallow water just off Rockaway Beach, Thursday, February 25, 2016, in the Queens borough of New York. Authorities say a Coast Guard vessel overturned while assisting the fishing boat that ran aground in an inlet off New York City. (Photo by Frank Franklin II/AP Photo)

A Syrian rebel walks past Sham 2, a homemade armored vehicle, in Bishqatin, Syria, on December 8, 2012. From a distance it looks rather like a big rusty metal box but closer inspection reveals a homemade armored vehicle waiting to be deployed. Sham II, named after ancient Syria, is built from the chassis of a car and touted by rebels as “100 percent made in Syria”. (Photo by Herve Bar/AFP Photo)

Relatives and friends react during the funeral of Bryan Sandoval, 17, a victim of a landslide that has left at least 112 dead and 350 missing people, in El Cambray II village, Santa Catarina Pinula, Guatemala, 04 October 2015. The landslide took place on 01 October 2015 when heavy rains saturated the soil. (Photo by Esteban Biba/EPA)

A mascot of the Philippine National Police (PNP), named after their Chief Director General Ronald Dela Rosa, marches with members of the K9 units and the Special Action Force before the mass blessing for rescue dogs during the celebration of the feast day of St. Francis of Assisi, patron Saint of Animals, at the St. John Paul II parish church in Eastwood, Quezon city, metro Manila, Philippines October 2, 2016. (Photo by Romeo Ranoco/Reuters)