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Life well lived: Cena, bomb-sniffing dog who served in Afghanistan, dies

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Hundreds of people lined the streets in Muskegon, Michigan, to honor Cena, a black Lab who served three tours of duty in Afghanistan with the Marines. He retired in 2014 and became a service dog to his former combat partner. In recent months, Cena was diagnosed with terminal bone cancer, and succumbed to the disease this week. He was 10 years old.