Lightning from a tornadic thunderstorm passing over Clearwater, Kansas strikes at an open field May 19, 2013. A massive storm front swept north through the central United States on Sunday, hammering the region with fist-sized hail, blinding rain and tornadoes, including a half-mile wide twister that struck near Oklahoma City. News reports said at least one person had died. (Photo by Gene Blevins/Reuters)

Young “scissors” dancers pose after performing in a national scissors dance competition at Lima's Exposition Park, May 18, 2014. The Danza de las tijeras, or scissors dance, is a traditional dance from the Peruvian southern region of the Andes, in which two or more performers take turns dancing while accompanied with music from a harp and a violin. Dancers would display various skills and moves, which include cutting the air with the use of a scissors. (Photo by Enrique Castro-Mendivil/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.

Only the most intrepid urban explorers cross the tattered ruins of the old Iron Curtain to endure the excessive bureaucracy, military paranoia and freezing winds of the East to hunt for the ghosts of an empire. Rebecca Litchfield is one who couldn’t resist the haunting allure of the ruins of the Soviet Union.

A group of surfers ride the Bore Tide at Turnagain Arm on July 15, 2014 in Anchorage, Alaska. Alaskas most famous Bore Tide, occurs in a spot on the outside of Anchorage in the lower arm of the Cook Inlet, Turnagain Arm, where wave heights can reach 6-10 feet tall, move at 10-15 mph and the water temperature stays around 40 degrees farenheit. This years Supermoon substantially increased the size of the normal wave and made it a destination for surfers. (Photo by Streeter Lecka/Getty Images)

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)

Interesting photos which can't be united in a certain series quite often come across to me. Therefore I publish simply a small group of separate pictures – enjoy, if it's interesting to you. Photo: “Road Trip!” (Photo by Thad Lawrence)

Revellers attend the Victorian Picnic during the Wave and Goth festival in Leipzig, Germany, May 22, 2015. The annual festival, known in Germany as Wave-Gotik Treffen (WGT), features over 100 bands and artists in venues all over the city playing Gothic rock and other styles of the dark wave music subculture. One of the biggest of its kind, the event attracts a regular audience of up to 20,000, the organisers said. (Photo by Hannibal Hanschke/Reuters)