Jimmy Arnold, an overweight boy from Rochester, bites into a cake. (Photo by Reg Birkett/Keystone/Getty Images). 14th April 1951

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.

Fishermen pull up a live 2.5 metre crocodile in their net in the Western Amazon region, Brazil on September 20, 2017. The fishermen were fishing for a large river fish called Arapaima but sometimes crocodiles become stuck in the nets as well. (Photo by Carl de Souza/AFP Photo)

People sit at an oversize picnic table in Soho Square in London May 19, 2014. (Photo by Luke MacGregor/Reuters)

Grumpy Cat attends the “Grumpy Cat: A Grumpy Book” Book Event at Bookends Bookstore on October 16, 2013 in Ridgewood, New Jersey. (Photo by Michael N. Todaro/WireImage)

A three-month-old Sumatran tiger cub named “Bandar” shows his displeasure after being dunked in the tiger exhibit moat for a swim reliability test at the National Zoo in Washington, on November 6, 2013. All cubs born at the zoo must take a swim test before being allowed to roam in the exhibit. Bandar passed his test. (Photo by Manuel Balce Ceneta/Associated Press)

A woman worker prepares her stall at Tanah Abang textile market in Jakarta, Indonesia January 11, 2017. (Photo by Fatima El-Kareem/Reuters)

A young evacuee of Japanese ancestry waits with the family baggage before leaving by bus for an assembly center in California, in this April 1942 handout photo. February 19, 2017 marks the 75th anniversary of FDR signing executive order 9066, authorizing the internment of Japanese Americans during World War Two. (Photo by Courtesy Clem Albers/Department of the Interior/War Relocation Authority/National Archives/Reuters)