The working Marine Corps dog known as "Sergeant Rex" - the subject of a book showcased at the 2012 Tucson Festival of Books - has died at age 11, after three combat deployments to Iraq.
Mike Dowling, Rex's first handler in Iraq, co-authored the book "Sergeant Rex: The Unbreakable Bond Between a Marine and his Military Working Dog." Readers packed into the festival's Arizona Daily Star Pavilion on the University of Arizona Mall to hear Dowling speak there last March.
Dowling and Rex were one of the first K-9 teams deployed for front-line duty in Iraq, where they survived their first firefight together in early 2004, as described in a Star feature early last year.
Rex, trained to detect improvised explosive devices, returned to Iraq on deployments in 2005 and 2006 with Cpl. Megan Leavey. The pair were working in Anbar province when Rex detected a buried bomb that exploded, wounding them both.
After the 2006 blast, Rex was "diagnosed with a little PTSD," Dowling has said, and the German shepherd served out his active-duty days at Camp Pendleton, Calif.
In 2011, Rex was flown to Tucson on a special detail to sweep the UA campus for explosives before President Obama's appearance there after the deadly shooting spree that wounded former U.S. Rep. Gabrielle Giffords.
The military released Rex to retirement in 2012, and he was adopted by Leavey.
This was posted on Rex's Facebook page after he died on Dec. 22: "Rest in peace Rex and thank you for your service and sacrifice. Once a Marine, Always a Marine ... Semper Fi."