Prince William exchanges rings with his bride Catherine Middleton in front of the Archbishop of Canterbury Rowan Williams inside Westminster Abbey on April 29, 2011 in London, England. The marriage of Prince William, the second in line to the British throne, to Catherine Middleton is being held in London today. The marriage of the second in line to the British throne is to be led by the Archbishop of Canterbury and will be attended by 1900 guests, including foreign Royal family members and heads of state. Thousands of well-wishers from around the world have also flocked to London to witness the spectacle and pageantry of the Royal Wedding. (Photo by Dominic Lipinski - WPA Pool/Getty Images)

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.

A cat Loki with a pair of distinctive fangs has quickly become one of the most famous felines on Instagram thanks to evil-looking face. Loki, who now has more than 23,000 followers online, was adopted from a cat shelter by her owner Kaet, who explained on in a posting that she knows very little about the cat’s distinctive appearance. Adopted from a cat shelter, nothing was mentioned to his owner Kaet about her kitten's unique features.

Michael Hughes creates cool optical illusions by placing cheap souvenirs in front of famous landmarks. Michael has discovered the technique back in 1998 when he held up a postcard he bought for his daughter on the tourist platform at the Lorelei cliffs next to the river Rhine. “I was amazed because it just seemed to fill a massive grey hole that was in the sky and it was the exact position the photographer had taken the picture from,” said Michael to Daily Mail.

A Dartmoor Hill pony foal runs on the moor on Dartmoor on May 17, 2011 in Princetown England. Although a tourist attraction, especially during the foaling season and often seen as part of the landscape of Dartmoor, many ponies face an uncertain future due to unsustainable breeding and their falling market values. The charity South West Equine Protection estimates that last year 1500 ponies were slaughtered – with many being sold for lion meat to nearby zoos. Along with other equine charities, they are calling for the removal of stallions from the moor to bring numbers down to sustainable levels. (Photo by Matt Cardy/Getty Images)

Models of Cold War-era Allied (L) and Soviet Bloc weaponry face one another at the new Bundeswehr Military History Museum (Militaerhistorisches Museum der Bundeswehr, or MHM) on October 11, 2011 in Dresden, Germany. The museum, redesigned by star architect Daniel Libeskind, traces Germany military history from 1300 to the present, including during the Nazi period and the Cold War, and also examines the influence of the military on popular culture. (Photo by Sean Gallup/Getty Images)

Barking mad owners have proved they really do look like their pets – by performing impressions of their own dogs. In a series of hilarious “paw”-traits, owners pull their best faces to look like their pooches. Snapped by photographer Ines Opifanti, people stuck their tongues out, yawned and tilted their heads in curiosity at the camera. Opifanti, from Hamburg, Germany, came up with the idea while interacting with her own dogs, two pug/French bulldog crossbreeds. Here: Amina and Zazou the dog. (Photo by Ines Opifanti/Caters News)

Roma people are seen in a Romani camp installed along La Petite Ceinture, an abandoned railroad line, in Paris, France, February 2, 2016. More than 350 Roma people, who have been living here since the last summer, face eviction from the makeshift camp this week. (Photo by Jacky Naegelen/Reuters)