AMARILLO, Texas (AP) — A electric and natural gas company has warned Texas and New Mexico customers to beware of pay-over-the-phone schemes.

Xcel Energy on Friday said that scammers are increasingly calling customers, pretending to be utility representatives and threatening to disconnect service unless payment is made over the phone.

Officials say business and residential customers have been targeted this winter. Scammers also sometimes send emails or confront customers in person. Bogus calls are often done on nights and weekends, not during regular business hours.

Xcel Energy spokesman Wes Reeves in Amarillo says customers who get such fake payment calls should hang up and contact the company. The utility sends written disconnect notices first, via the U.S. Postal Service, if a customer is in danger of losing serving for nonpayment.