JJ the bloodhound - who sniffed out and tracked down nearly 300 criminal suspects during his nine-year career with the Salt Lake City Police Department - died Thursday of cancer.
The 10-year-old dog was diagnosed more than a year ago with a malignant melanoma in his mouth.
He succumbed despite a series of trips to New York City for surgery and experimental radiation treatment. But the aggressive medical treatment did extend JJ's life, as well as his career as a police dog.
Even after being diagnosed with cancer, JJ helped apprehend close to 50 suspects, tracking one of them for almost three miles, according to Salt Lake police spokesman Jeff Bedard.
"He was able to put a lot of dangerous people in jail . . . people that we couldn't find on our own as police officers," Bedard said Friday.
JJ's handler, K-9 Officer Mike Serio, pioneered the use of bloodhounds when most Wasatch Front police departments relied almost exclusively on German shepherd dogs. Matt Jewkes, a K-9 handler for South Salt Lake police, said the German shepherd handlers sometimes bragged their dogs could track better than JJ, but JJ usually outperformed them.
Jewkes said JJ's handler "was a huge influence and proved they were valuable dogs to have."
Jewkes gives Serio credit for JJ's success, saying Serio treated the dog like one of his family. He recalled once seeing Serio walk out of a restaurant with a blueberry muffin and feed it to JJ in his police car. Most police dogs are on a strict diet, but Serio stayed close and affectionate with JJ.
"You're going to get out of your dog what you put in your dog," Jewkes said.
Serio was a patrol officer when he bought JJ as a pet at the age of 8 weeks. Serio later noticed that JJ liked to track people around his house. And when the dog turned 1, Serio started playing hide-and-seek with him.
Serio eventually proposed to the department that JJ become a police dog. Serio retained ownership and was reimbursed for the dog's use and expenses. At night, JJ slept on or at the foot of Serio and his wife's bed.
Serio was not available for immediate comment Friday.
"We're trying to give him a little time to mourn and grieve in private," said Bedard, who added that the mood on Friday at the police department was "pretty somber."
"For almost 10 years, JJ has not just been a police service dog, he's been a real member of our family," Bedard said. "A lot of people have had a lot of good experiences with JJ and he'll be tremendously missed."
Bedard noted that even in the midst of cancer treatments, JJ "came back to work dutifully almost every night. It shows he really had a passion for what he did. And Mike had a passion for it, as well."
Because of JJ's success, Salt Lake City police have added two more bloodhounds to their K-9 team, and police in South Salt Lake and South Jordan have bought their own bloodhounds.