They're considered man's best friend, but dogs are also a key resource in fighting crime and terrorism in our local police departments.

News 12 Long Island's Jill Wagner got an exclusive look at how the dogs in Suffolk County's police K-9 unit are trained to prevent terrorism.

Suffolk Police Chief Stuart Cameron says that since the Boston Marathon bombings in April, the request for dogs to perform anti-terror security checks has risen exponentially.

Officer Michael Cassidy's partner, Thor, is just one of 22 dogs in the Suffolk County Canine Unit. Cassidy says Thor and his four-legged friends are crucial tools as the department works to prevent terrorism.

Dogs like Thor are trained to hone in on the scents associated with explosives. Cassidy says the canines are put through rigorous tests that include distractions to better prepare for real-life scenarios. The dogs go through almost 300 hours of training before they're certified in explosives detection.

And when training is over, Thor and his friends are rewarded with praise and some play time.

Cassidy says working with dogs is a true partnership, "I trust him with my life."

For more of our exclusive look at the Suffolk K-9 training facility, head to channel 612 and click on the News 12 Extra tab.