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.

An American flag flutters on a young tree stripped of bark after a massive tornado passed through the town killing at least 116 people May 24, 2011 in Joplin, Missouri. The tornado that ripped through the town of about 50,000 people May 22, is being called the deadliest single tornado in the U.S. in 60 years. (Photo by Julie Denesha/Getty Images)

“Kim Jong-il, also written as Kim Jong Il, birth name Yuri Irsenovich Kim (according to Soviet records) (16 February 1941/2 – 17 December 2011), was the supreme Leader of the Democratic People's Republic of Korea (North Korea). He was the General Secretary of the Workers' Party of Korea, the ruling party since 1948, Chairman of the the National Defence Commission of North Korea, and the Supreme Commander of the Korean People's Army, the fourth-largest standing army in the world”. – Wikipedia

Photo: North Korean leader Kim Jong Il inspects a military unit in North Korea. (Photo by Korean Central Television/Yonhap)

Uma Thurman visits 'Late Night with Jimmy Fallon' at Rockefeller Center on April 8, 2011 in New York City.

A police officer jump ropes with a police dog at a police dog training base on July 11, 2011 in Beijing, China. The Police Dog Training Base was opened to a media visit to show the dogs skills to the public. (Photo by ChinaFotoPress/Getty Images)

“Photographer Seth Casteel has definitely taken animal photography to new heights – or depths – with his hilarious photos of dogs chasing balls underwater. Casteel, who, naturally, has two dogs of his own (a mini Labradoodle and a Norwich terrier), said that he's drawn to underwater dog photography because the photos show a side of dogs that people may have never seen before”.

Photo: Seth Casteel Underwater Dog Pictures (Photo by Seth Casteel)