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.

Members of the Royal Navy respond to a simulated fire in a Vanguard-class submarine control room training facility at Clyde naval base in Faslane, Scotland on January 21, 2016. (Photo by Photograph: Danny Lawson/PA Wire)

A woman with a sign that reads in Portuguese “Being woman without Temer”, stands next to a police barricade during a protest against the gang rape of a 16-year-old girl in Sao Paulo, Brazil, Wednesday, June 1, 2016. In response to the assault, Brazil's interim President Michel Temer said that the country will set up a specialized group to fight violence against women. (Photo by Andre Penner/AP Photo)

Californian photographer and conservationist Octavio Aburto had spent years photographing the school in Cabo Pulmo National Park, Mexico – and had been trying to capture this exact shot for three years. “Together with my friend David Castro, we were diving with a large group of Bigeye travellies at Cabo Pulmo National Park, Mexico. Thousands of fish forming a ball during the reproduction courtship. In the afternoon, these fish congregate to form a large spawning aggregation around the reefs of the National Park”. (Photo and caption by Octavio Aburto)

Trained by Dutch photographer Ellen van Deelen to hold different musical instruments and pose for the camera, the Roosendaal Rats are considered very talented by their owner. She confesses rats weren’t exactly her favorite creatures, but, after buying these two, she realized they are highly intelligent creatures.

A genetically engineered featherless rooster struts around the campus of the Hebrew University of Jerusalem's Department of Agriculture May 22, 2002 in Rehovot, Israeli. After two years of research, departmental scientists announced the naked chicken, as it has been dubbed, as a low calorie bird because the lack of feathers means the chicken has less fat. It also matures earlier than its feathered counterparts. (Photo by Moshe Milner/GPO/Getty Images)

Mount Sinabung is seen during an eruption from Surbakti village in Karo, North Sumatra, Indonesia, April 20, 2015. The local government is preparing the relocation of residents from three of the villages that were destroyed. (Photo by Tibta Pangin/Getty Images/Anadolu Agency)

Yannis Behrakis, one of Reuters' most decorated and best-loved photographers, has passed away after a long battle with cancer. He was 58. Here: A pro-government Sierra Leonean fighter bites a bullet as he takes position in no man's land 2 km ahead of Rogberi junction where evidence of executed UN troops were found after heavy fighting between government troops and RUF rebels 100 km north east of Freetown, Sierra Leone, May 23, 2000. (Photo by Yannis Behrakis/Reuters)