A woman claiming to be an AT&T representative called Alex Garcia about a week ago and warned him his cell phone was going to be disconnected because of a late payment. She offered to waive the $35 disconnect fee if he paid over the phone.

Because AT&T’s number appeared on his caller ID, Garcia took out his credit card … then asked why she did not have the information already.

When the woman got upset, Garcia, a Honolulu Police Department detective, realized it might have been a scam and hung up. He called AT&T, which said his account was not late and that no one from the company had called him.

"It’s fortunate they called the real ‘Hawaii Five-0’ detective," he said, adding that he hopes to warn the public about the scam. "It’s important that people be aware of this scam that’s going on so they don’t get a financial loss, especially so close to the holidays."

Like Garcia, more people in Hawaii are becoming targets of call "spoofing," the act of disguising the origin of the call by sending a different phone number to a person’s caller ID. Call spoofing is not illegal, but swindlers can use it to trick people into giving up personal or financial information.

Tom Simon, an FBI special agent in Honolulu, said call masking and other phishing scams, such as using authentic-looking fake websites, e-mails or text messages to fool victims into giving up private information, are growing across the country as technology gets cheaper. However, scams using call masking are not a major problem in Hawaii, he said.

A caller can "spoof" a recipient’s caller ID by buying an account online, like a calling card, or using a website that allows the user to do it for free. The caller chooses the number to appear on the caller ID before making the call.

One website that sells spoofing accounts, spoofcard.com, says a few states have banned spoofing for certain purposes, such as "to mislead, defraud or deceive the recipient of a telephone call."

Chris Duque, a retired Honolulu police detective and Internet security expert, said spoofing has been around for several years and has been used by bill collectors, law enforcement and bail bondsmen.

Police might use it to check whether a subject’s phone number is still working – a technique called "pretexting."

But spoofing is being used largely for unethical purposes, he said.

"The bad guys are using it much more often than legitimate businesses," he said.

Duque said spoofing might be on the rise as fraudsters resort to using phones and reg-ular mail to avoid law enforcement, which is focused more on e-mail and the Web.

Earlier this month, Big Island police said, a Hilo woman gave her debit card information to a caller pretending to be an AT&T representative. The caller said the woman’s check had been unsigned and even had the check number.

After giving her bank information, the victim learned her check had cleared and that no one from AT&T had called her. The scammer made off with $348 from her account.

Police said the woman could not recall whether her caller ID showed AT&T’s telephone number.

An AT&T spokeswoman said the company is aware of the spoofing scam and advised customers to use caution if they receive an e-mail, phone call or text message requesting personal or credit card information.

At Hawaiian Telcom, spoofing is a growing problem. The company’s nuisance call bureau receives a few complaints a week and has seen a rise in complaints about call spoofing this year, said spokes-woman Ann Nishida Fry.

She said callers using a fake caller ID have phoned residents and businesses and often impersonate banks and phone companies.

According to the Federal Communications Commission, Congress is looking at outlawing call spoofing. Telemarketers are already banned from spoofing or blocking a caller ID, and violators can be fined.

Nishida Fry said that in some cases the call can be traced, although that might require cooperation from other networks and providers.

While caller ID has a lot of advantages, she said, it is not foolproof, and the best safeguard remains awareness and self-protection. She said legitimate businesses do not request sensitive information over the phone, and people should not give it out.

As for Garcia, the would-be victim, he warned people to be cautious about the scam because they might not realize they have been scammed until weeks later, when the phone company calls because their bill really is overdue.

"I’d be double-whammied," he said.