It's a bitter cold morning and the phone rings, and the caller is threatening to cut off your power immediately if you don't pay hundreds of dollars in late power bills. What do you do?

The answer is to call law enforcement immediately, according to Northwestern Energy spokesman Butch Larcombe.

"Nobody from Northwestern Energy will call you out of the blue and say you need to pay your bill immediately or we'll cut off your power," Larcombe said. "We'll call, send letters, we'll knock on their door and go to great lengths before we even get close to cutting off someone's power, and during certain times of the year, we just won't. The fact that people are in such a hurry and are creating a big sense of urgency should be a tip-off."

Larcombe said such a scam call is not just a nuisance, it is a crime.

"You should call law enforcement right away, because this is a crime, and like any other crime it should be reported," he said. "There are probably some limits as to what law enforcement can do, but they are very interested to learn the pattern of that particular scam. We work with them and other federal agencies to prevent this sort of thing."

Larcombe provided a number at Northwestern Energy to call if a scammer targets a Montana citizen, it is 1-888-467-2669.