FORT JACKSON, S.C. (Feb. 21, 2013) -- "Gabe took his last breath at 12:44 p.m. while I held (him) in my arms."With those words, Sgt. 1st Class Charles "Chuck" Shuck notified thousands of online followers that his dog, Gabe, had passed away. The notice received almost 5,000 direct comments on Facebook from fans who have followed Gabe during his campaign last year for the American Humane Association's Hero Dog Awards. It was a competition that put him against working dogs from all walks of life, and his victory in October ultimately won thousands of dollars for the nonprofit United States War Dog Association. In recent months, his "Hero Dog" standing also put him in the same room with celebrities like Betty White and Jay Leno.Just a few years ago, though, his life was less glamorous. Rescued from an animal shelter in Texas, Gabe was trained to become a military working dog, eventually deployed to Iraq where he spent his days searching for explosives, ammunition and other weapons. He racked up 26 "finds" during the 170 combat patrols he took part in, the largest of which was a cache of rounds discovered on the banks of the Tigris River.He retired in 2009 at the rank of sergeant first class. Shuck said he took Gabe to Spring Valley Animal Hospital Feb. 12 after the dog refused to eat "for the first time ever." Veterinarians determined the dog was suffering from cancer in his liver and spleen. By the time the illness was detected, Shuck, a drill sergeant leader with the Drill Sergeant School, said it was too late to treat the illness.He opted to have the dog put to sleep.Shuck said Gabe was surrounded by his favorite toys and medals when he died. He was 10 years old."He went into shock and they gave him transfusions of plasma that night, but he never recovered," Shuck said. "He's pain free, and that's the solace I'm taking for today.""Shuck and Gabe both risked their lives in service to our nation," said Robin Ganzert, president and CEO of the American Humane Association. "In turn, their service saved the lives of many men and women of our armed forces. Our condolences go out to Sgt. 1st Class Chuck Shuck. But this I know in my heart, even through Gabe has crossed the rainbow bridge, he will live on in the hearts of all of us who fight to give voice to the voiceless and bring love and compassion to at-risk children and animals."Shuck was paired with Gabe in 2006, with Gabe passing his final military evaluation in Numa, Az., after five months of training. A few weeks later the two found themselves on the ground in Iraq. When Gabe left Iraq, he took with him three Army Commendation Medals and an Army Achievement Medal from the different units, and dozens of coins of excellence.Gabe received the 2008 Heroic Military Working Dog Award Medal from the American Kennel Club, a national award that included animals from all armed forces.Shuck was allowed to adopt Gabe in 2009."We're just asking people to continue to support Soldiers and military working dogs who are still fighting right now overseas," he said.Gabe will remain the American Humane Association's 2012 Hero Dog through October, Shuck said. There are no plans to replace him.