The PAWS shelter in Lynnwood, Wash., is filled with dogs of all shapes and sizes, from young puppies to aging pooches and purebreds to mutts. Most of the dogs in the shelter ended up there because they were either abandoned or were considered too difficult to handle in one way or another.

For K-9 trainer Melissa Larsen, however, the shelter is the perfect place to find dogs that will, ultimately, dedicate their days to saving human lives. She goes to the shelter to look for dogs with a keen sense of smell and a powerful hunting instinct. Basically, she wants dogs that are highly focused, yet still trainable, reported USA Today.

"You know there's plenty of hunting breeds out there that are discarded in the shelters, and it's usually because they are too active and too high-strung and too obsessive, which is exactly what I like," she said.

After rescuing a dog from the shelter, Larsen intensively trains them in the art of finding explosives. Using a reward system, she was able to train a number of dogs that were eventually taken in by police departments.

Boomer was a dog who journeyed from shelter to shelter, looking for a forever home. After Larsen's training, he was given to the Seattle Police Department, where he became a superstar.

"He's phenomenal. He's wonderful. What we look for [are] dogs that will be at the end of the leash and, no matter where you go as the handler, that dog is always working and that dog is going to save your life," said Larsen.

Boomer's handler, Det. John Lewitt, said that the dog has a special gift for finding weapons or explosives. In fact, Boomer's success in the program has paved the way for other rescue dogs who do not get adopted to follow in his path.

Other dogs will be joining Boomer's Seattle Police Department squad soon, including Jazzy and Storm. And Harley is headed to the UW police Department.

Boomer and his fellow rescues were dogs that didn't fit in and now they are making our world safer.

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