Stephen Chernin / AP

Trained as a police dog in Halifax, Nova Scotia  where he worked for six years, helping to find more than $1 million in contraband  Trakr had retired in May 2001 before he and his trainer, Canadian police officer James Symington, drove 15 hours to help recovery efforts in New York City following the Sept. 11 attacks. Trakr was credited with locating the last survivor found beneath the rubble. Two days after arriving and searching for survivors the entire time, Trakr collapsed from smoke inhalation, exhaustion and burns and was treated for his injuries before returning to Canada. Later in life Trakr suffered from a degenerative neurological disorder that experts say could have been caused by his work at Ground Zero. Before Trakr died in April 2009, his DNA was entered into a cloning contest by Symington and was later chosen for use. In June of that year, five cloned Trakrs were born.

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