A boy runs with a burning barrel soaked in tar at the annual Ottery St Mary tar barrel festival on November 5, 2015 in Ottery St. Mary, England. The tradition, which is over 400 years old, sees competitors (who must have been born in the town to take part) running with burning barrels on their backs through the village, until the heat becomes too unbearable or the barrel breaks down, starting with junior barrels carried by children and continuing all evening with ever larger and larger barrels. The event, which has been threatened with closure on previous years due to increasing public liability insurance costs, raises thousands of pounds for charity and attracts spectators from around the world. (Photo by Matt Cardy/Getty Images)

A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Runners gather at the start line for the annual “Santa Speedo Run”, a charity race through the streets of the Back Bay neighborhood of Boston. (Photo by Gretchen Ertl/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.

Thai military officers dressed in traditional orange monk robes arrive to attend their official ordination ceremony on July 13, 2011 at the Benchamabopit temple, also known as Marble temple, in Bangkok, Thailand. Eighty four of the military officers were ordinated into the Buddhist community over two days, taking leave of absence from their jobs in the Army for three months during the Buddhist lent period. July 16 will mark the first day of the yearly three-month retreat of Buddhist monks where they will practice meditation in temples and study dharma. (Photo by Paula Bronstein /Getty Images)

See What Happens when This Cat Enjoys a Less Than Tasty Meal

Ethiopian Orthodox worshippers celebrate the Holy Fire ceremony at the Ethiopian section of the Church of the Holy Sepulcher on April 23, 2011 in Jerusalem's Old City, Israel. Hundreds of Orthodox Christians, all from different sects, participated in the ceremony a day preceding Orthodox Easter, and has been celebrated by worshipers for the last 1,200 years. (Photo by Uriel Sinai/Getty Images)