Costumed revelers pose in front of the Chapell bridge on the opening day of the carnival in Lucerne, Switzerland, 20 February 20​20. The carnival takes place in Lucerne from 20 to 25 February 2020. (Photo by Alexandra Wey/EPA/EFE)

A dog plays with a giant soap bubble in downtown Kiev, Ukraine, 06 March 2020. (Photo by Sergey Dolzhenko/EPA/EFE)

A health official checks the body temperature of a burqa-clad woman passenger amid concerns over the spread of the COVID-19 novel coronavirus at the Lahore Railway station in Lahore on March 19, 2020. (Photo by Arif Ali/AFP Photo)

Sofia Valenzuela poses during a photo session for her quinceanera (coming of age of 15-year-olds) celebration amid coronavirus disease (COVID-19) spread concerns, in Havana, Cuba, July 17, 2020. (Photo by Alexandre Meneghini/Reuters)

In this photo provided by The Daily Free Press and Kenshin Okubo, people react to an explosion at the 2013 Boston Marathon in Boston, Monday, April 15, 2013. (Photo by Kenshin Okubo/AP Photo/The Daily Free Press)

P.S. All pictures are presented in high resolution.

British model Jean Shrimpton at London Airport (now Heathrow), 5th June 1967. (Photo by Dove/Express/Getty Images)

Storm clouds gather over the scene outside the Jewish Community Center in Leawood, Kansas following a shooting, on April 13, 2014. (Photo by John Sleezer/Kansas City Star/MCT)

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.