A conductor (C) collects fares from candy floss sellers as they travel in a tram to a marketplace early morning in Kolkata, India, December 23, 2015. (Photo by Rupak De Chowdhuri/Reuters)

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 female participant of the Bela Negara – “defend the nation” – programme applies camouflage face paint on another participant's face at a training centre in Rumpin, Bogor, West Java, Indonesia June 2, 2016. (Photo by Darren Whiteside/Reuters)

A member of the Revolutionary Armed Forces of Colombia (FARC) pose for a picture at a camp in the Colombian mountains on February 2005. (Photo by Frank Piasecki Poulsen)

A person viewing the Northern lights over the lava landscape, Reykjanes Peninsula, Iceland. (Photo by Arctic-Images/Getty Images)

Rummaging in a bin for scraps, this fox in Barnet, north London, England found itself trapped in the lid on May 23, 2019. Luckily the Royal Society for the Prevention of Cruelty to Animals were able to free it. (Photo by RSPCA/PA Wire Press Association)

Donald Trump is flanked by Playmates at a party celebrating Playboy magazine's 45th anniversary at the Life Club in New York on December 3, 1998. (Photo by Richard Corkery/NY Daily News Archive via Getty Images)

Randy Orton is seen in action against Rey Mysterio during the single match of WWE “Crown Jewel” World Cup 2018 tournament at King Saud University stadium in Riyadh, Saudi Arabia on November 2, 2018. (Photo by Faisal al Nasser/Reuters)