By Molly Daly

PHILADELPHIA (CBS) — Police in southern New Jersey are warning about scammers targeting small businesses with threats to cut off their power unless they’re paid immediately.

Medford Township Police Lieutenant Arthur Waterman says they’ve gotten five complaints in the past week about the scammers claiming to be with the IRS or PSE&G.

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“Criminals are contacting businesses, indicating that they’re delinquent on either on their taxes or their utility bill,” Waterman said, “and requiring payment.”

They want their marks to do that with prepaid debit cards, which are tough to track. One business was swindled out of close to $4,000. Waterman says the flim flammers are aggressive, threatening and resourceful.

“Don’t trust your caller I.D.,” he warned. “They have ways with technology, ways that they can spoof numbers so they can make it look like something that it isn’t.”

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He says the best approach is to contact the actual company they claim they represent.

“Always follow up,” Waterman said. “If they say you owe money, then they can wait ten minutes for you to verify with the company, calling the company yourself to make sure it’s a legitimate phone call.”

Karen Johnson of PSE&G says that customers who are behind on their payments are notified by a message on their bill, then by letter, then by a phone call. She says they wouldn’t demand the amount be paid immediately.

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“The utility offers a number of payment options,” Johnson said, “but we would never require a customer to use one specific type of payment, such as a prepaid card.”