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Chicago police Officer Michael Walters took his K-9 partner, Bob, 7, to be put down due to brain cancer at Niles Animal Hospital in Niles on Dec. 7, 2016.
Chicago K-9 put down
Stacey Wescott / Chicago Tribune
Chicago police Officer Michael Walters walks his K-9 partner, Bob, 7, into the Niles Animal Hospital for the last time before she is put down Dec. 7, 2016. 
