A scheme to obtain US WEST Communications telephone credit card numbers from the company's customers and then sell the numbers to other people has been uncovered, officials said Thursday.

"It started in Utah about three days ago," said Carol Dunlap of US WEST, formerly Mountain Bell. The callers identify themselves as US WEST Communications investigators trying to track down illegal use of credit cards, she said."They're using various tactics in order to get the person's credit card number," she said. "The most common is suggesting someone is using the person's credit card number to call England and they need to confirm the number in order to get it stopped."

The numbers then are sold to other people, she said, adding, "some US WEST customers in other states have received phone bills for $3,000 to $4,000. They were victimized and didn't know it until they got their phone bill."

The company's employees "would never ask for a telephone credit card number," Dunlap said. "If someone calls claiming to be with US WEST Communications or Mountain Bell, customers should refuse to give out the information and report the incident to their local telephone business office."

US WEST has an investigative team attempting to track down the scheme operators, she said. They will be able to trace calls back to people who purchased credit card numbers and hope the people will identify the sellers.