An Afghan girl carries water on her back as she climbs a hill in Kabul, Afghanistan February 20, 2017. A growing population is straining water supplies in Afghanistan's capital, forcing those who can afford it to dig unregulated wells ever deeper to tap a falling water table. Finding water in arid Afghanistan is virtually always a challenge, but a drop in the groundwater level in Kabul caused by overuse and drought is making it even more difficult for residents, especially the poor. (Photo by Omar Sobhani/Reuters)

The dashboard of a 1980 Teal Type 35 Bugatti (estimate £28,000 - £35,000) on display inside the Royal Horticultural Halls on April 11, 2017 in London, England. Coys automobile auctioneers are putting almost 70 classic cars up for auction in their Spring Classics sale in Westminster tomorrow, April 12, 2017. (Photo by Jack Taylor/Getty Images)

Visitors view the work entitled “Golden Jubilee” by Chinese artist Xin Dongwang at the “Extension and Integration: A Circuit Exhibition In Hubei Of Study on the Modern Chinese Oil Painting” at the Hubei Museum of Art on March 8, 2009 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

Frida Karlsson takes 2nd place, Therese Johaug of Norway takes 1st place, Ingvild Flugstad Oestberg of Norway takes 3rd place during the FIS Nordic World Ski Championships Women's Cross Country Classic on February 26, 2019 in Seefeld, Austria. (Photo by Lisi Niesner/Reuters)

A woman looks out of the window of a house as saris, traditional clothing worn by women, are hanged out to dry in Lalitpur, Nepal on April 17, 2019. (Photo by Navesh Chitrakar/Reuters)

Indian School children's in a traditational attire of a characters of Indian epic Ramayan, on the eve of children's day celebration at cubbon park, in Bangalore, India, 13 November 2016. Children's day (also known as Bal Divas), in India is celebrated every year on 14th of November to increase the awareness of people towards the rights, care, and education of children. Many schools hold activities and allow students to have fun and attend their classes in coloured dresses. (Photo by Jagadeesh N.V./EPA)

Kieron Connolly’s new book of photographs of more than 100 once-busy and often elegant buildings gives an idea of how the world might look if humankind disappeared. Here: Bodie, Mono County, California. Gold was discovered at Bodie in 1859 (just after the initial California gold rush) and it went from mining camp to boomtown. Its decline began in 1880, when word spread of new boomtowns elsewhere. The Standard Consolidated Mine closed in 1913, and four years later the Bodie Railway was abandoned. By 1940 the population was down to 40. Today, Bodie is maintained in a state of arrested decay as a visitor attraction. (Photo by Alamy Stock Photo)

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.