New Hampshire State Police (NHSP) responded to reports Tinsley, a German Shepard, was on the loose around the Veteran’s Memorial Bridge near the New Hampshire-Vermont border.

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Trooper Tom Sandberg and officers from the Lebanon Police Department found the canine wandering on the highway, looking skittish and scared, said NHSP Lt. Dan Baldassarre told CNN.

“They were trying to get the dog off of the highway to keep it safe,” he said.

When the authorities tried to get close to Tinsley, she ran away and headed northbound on the interstate. The officers followed the hound and discovered a damaged section of guardrail.

The police came across a badly damaged pick-up truck that had rolled over and saw two men thrown from the car, injured, and suffering hypothermia, the police department wrote on Facebook.

Medical assistance was called and officers learnt Tinsley belonged to one of the injured passengers.

“This was almost like a real-life Lassie situation,” NHSP public information officer Amber Lagace said in an email to CNN.

“It’s really quite remarkable. This dog definitely saved their lives. I don’t think they would have survived the night given the temperatures”

According to Vermont State Police, both passengers were taken to an area hospital for treatment. Tinsley did not appear to be injured in the crash.

“She’s my guardian angel,” Tinsley’s owner, Cam Laundry, told CNN affiliate WPTZ.

“It’s a miracle that she had that kind of intelligence to do what she did.”

Mr Laundry, who was driving the car, and his passenger, Justin Connors, are recovering from their injuries, Laundry told NECN.