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.

History Created on 15th June 92 Young poor & Physically challenged Couples tied in a lifelong knot of Marriage “Free of Cost” Combined Marriage Function at Ramlila Ground on behalf of “Narayan Sewa Sansthan”. “Although we are unable to move without the support of a crutch or might take the help of others in performing every activity, still, we can afford to become a support for each other”. With this spirit, 92 young disabled and poor brides &bridegrooms promised to support each other throughout their life. The historical Ramliila Ground of Delhi became the witness of this mega event. Photo: Mass wedding in Delhi.

The Spanish photographer Xavi Bou digitally combines sequential pictures of birds to create a single image, or chronophotograph, that reveals the shapes of their flight paths against Catalonian skies. His work shows the variety and beauty to be found in the daily activities of the local birds, including spiralling storks, swooping starlings and giddy swifts. Here: European herring gulls at Llobregat Delta. (Photo by Xavi Bou/Rex Features/Shutterstock)

Voodoo pilgrims bathe in a waterfall believed to have purifying powers during the annual celebration in Saut d' Eau, Haiti, Saturday, July 16, 2016. Annually, the falls are the site of a large, important religious pilgrimage, during the festival of Our Lady of Carmel, from July 14–16. A Eucharistic rite is held during the festival, as well as various vodou rituals, but the penultimate devotional activity is bathing in the waters of the falls, and asking favors of the Virgin or Erzulie. After bathing, voodoo pilgrims throw away the dresses they wore to the site, and don new clothes for good luck. (Photo by Dieu Nalio Chery/AP Photo)

Redhead Day (Roodharigendag in Dutch) is the name of a Dutch summer festival that takes place each first weekend of September in the city of Breda, in the Netherlands. The two-day festival is a gathering of people with natural red hair, but is also focused on art related to the colour red. Activities during the festival are lectures, workshops and demonstrations which are aimed specifically at red-haired people. The festival attracts attendance from 50 countries and is free due to sponsorship of the local government.

Martin Rietze is a “volcano-chaser”, a particular breed of photographer who takes big risks for big shots. He was able to capture destructive and beautiful forces of nature at work on a trip to Japan in February 2013. His photos show the Sakurajima Volcano, an active volcanic who's record-breaking 1914 eruption sent lava flows across the island. (Photo by Martin Rietze/Guzelian)