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.

Star Wars collector James Burns, 44, poses for a photograph with some of his collection in London December 2, 2015. He said “I've met so many wonderful people, all over the world. It's a wonderful community of likeminded people with an interest in Star Wars. There's nothing else like it”. (Photo by Paul Hackett/Reuters)

“Sektor gaza” (Russian: Сектор газа) was a Russian rock band formed on 5 December 1987 in the city of Voronezh, Russia. Despite only semi-officially existing (due to obscene lyrics), the group remains popular in Russia today. The group name was taken from an eponymous industrial district of Voronezh (itself named for high levels of environmental contamination). Their music style could be defined as Russian punk, integrated with elements of different musical genres such as rock, rap, and Russian folk. On 4 July 2000, group leader Yuri “Hoy” Klinskih complained of strong pains in his stomach and the left side of his chest. He suffered heart failure shortly thereafter. Klinskikh died in Voronezh (Russia)at the age of 35. He is buried in the Levoberezhniy Cemetery. The group ceased to exist.

About the music video: The First Chechen War, also known as the War in Chechnya, was a conflict between the Russian Federation and the Chechen Republic of Ichkeria, fought from December 1994 to August 1996. After the initial campaign of 1994 – 1995, culminating in the devastating Battle of Grozny, Russian federal forces attempted to seize control of the mountainous area of Chechnya but were set back by Chechen guerrilla warfare and raids on the flatlands in spite of Russia's overwhelming manpower, weaponry, and air support...

Kate Upton walks the runway at the Beach Bunny Swimwear show during Merecdes-Benz Fashion Week Swim 2012 at The Raleigh on July 15, 2011 in Miami Beach, Florida. (Photo by Frazer Harrison/Getty Images for Beach Bunny)

A Yorkshire Terrier has it's hair done on a grooming table on Day one of Crufts at the Birmingham NEC Arena on March 8, 2012 in Birmingham, England. During the annual four-day competition nearly 22,000 dogs and their owners will compete in a variety of categories, ultimately seeking the coveted prize of “Best In Show”. (Photo by Dan Kitwood/Getty Images)

A dejected German Grenadier carrying a machine gun on his shoulder in front of a building on fire during the German retreat in Russia. (Photo by Keystone/Getty Images). 1944

A Free Syrian Army fighter walks past a flag of al-Furqan brigade as a rifle hangs from a branch in the orchards of Kafar Zita in Hama countryside January 22, 2015. (Photo by Mohamad Bayoush/Reuters)

A clothing shop displays its merchandise in the rebel-controlled city of Idlib, Syria November 7, 2015. (Photo by Ammar Abdullah/Reuters)