Hawaiian Electric Co. is warning customers about a phone scam involving the use of fake caller ID and requests for money vouchers.

According to a news release issued Monday by HECO, dozens of small-business customers — mostly restaurants — recently reported receiving telephone calls in which the caller said an electric bill is delinquent and that the customer would be subject to same-day disconnection.

In some cases the customers also reported that caller ID showed the calls were from Hawaiian Electric. In each case the calls were not made by Hawaiian Electric, Maui Electric or Hawaii Electric Light Co., indicating the scammers were using commercially available technology to emulate legitimate caller ID.

Also, electric customers have reported that callers directed them to pay their utility bills by purchasing certain types of money vouchers called MoneyPak. This is not a legitimate method of making payments on electric bills.

Jim Alberts, Hawaiian Electric senior vice president for customer service, said, "These scams are growing increasingly sophisticated. The best defense is to exercise caution. We encourage our customers to remain alert and continue to report any suspicious activity."

Customers receiving a suspicious call from someone claiming to represent HECO are advised to call their respective Customer Service Centers: Oahu, 548-7311; Maui, 871-9777; Molokai and Lanai, 877-871-8461 (toll-free); Hilo, 969-6999; Kona, 329-3584; and Wai­mea, 885-4605.

In addition, Hawaiian Electric is reminding customers not to provide personal, confidential or financial information to any unidentified person and urges customers to exercise caution when responding to phone calls from unidentified people. If customers feel unsure about the identity of a caller, they should feel free to hang up and call their utility’s Customer Service Center and report any suspicious activity to police.