According to an agency Facebook post, Robbie's handler, Trooper Dave Chatfield, was conducting a vehicle search near mile marker 266 on Interstate 80 -- about six miles west of Arlington -- when he found a controlled substance.
He then unleashed Robbie and had him sniff around inside the vehicle to see if there was any additional contraband.
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When Chatfield reached for Robbie to reconnect his leash after the dog had finished his search, Robbie jumped out of the vehicle and ran into the interstate.
Sadly, Robbie, who had only been patrolling with Chatfield for a couple of months, was struck by a semi and killed instantly.
The patrol says the trucker "was not in violation of any laws at the time of the collision and no charges were filed."
Meet the Four-Legged Heroes of the Cheyenne Police Department
They may not be able to leap tall buildings in a single bound, but make no bones about it, police dogs play a vital role in the fight against crime.
In many situations, they're the first ones to put their lives on the line to protect their human partners, proving that not all heroes wear capes, some wear fur coats.
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Does your loyal pup's breed make the list? Read on to see if you'll be bragging to the neighbors about your dog's intellectual prowess the next time you take your fur baby out for a walk. Don't worry: Even if your dog's breed doesn't land on the list, that doesn't mean he's not a good boy--some traits simply can't be measured.
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