By week's end, the Division of Workforce Services plans to send out about 100 letters to Utahns whose children's Social Security numbers are believed to have been compromised by identity thieves - in many cases, immigrants working in the country illegally.

The 100 letters this week are just the beginning; many more letters likely will go out as state computer cross-referencing reveals potentially illegal use of the Social Security numbers, Workforce Services spokesman Curt Stewart said Tuesday.

In all, an estimated 20,000 of the numbers belonging to Utahns may have been compromised, he said. The first group to be addressed includes Utahns on public assistance whose applications for aid could potentially be impacted by the fraud.

"The letters to go out later this week are specifically to people on public assistance who have children under 14 [with Social Security numbers] collecting at least $1,000 in the last quarter," Stewart said.

The warnings are made possible by the passage of Senate Bill 15 during the last legislative session, he said. The new law allows Workforce Services, for the first time, to share its data on compromised Social Security accounts both with affected individuals and law enforcement.

"In the past we had found times when wages were reported [on stolen Social Security numbers] and we couldn't legally do anything about it," Stewart said. "But the newly modified Employment Security Act changed that, allowing us to disclose identity theft fraud."

Identity thieves can use the numbers for much more than collecting wages. The numbers also can be used to apply for credit cards, loans and other transactions that can leave the legitimate holder of the Social Security account with destroyed credit and bill collection headaches.

"We're finding out a lot of young people are having their Social Security numbers stolen. They get to the age of 18 and go to get a student loan or buy a car and find their credit history is already wrecked," said Chief Deputy Attorney General Kirk Torgensen.

"Our real concern was we didn't want parents and their kids to find out something like this too late," he added.

Last December, stolen Social Security numbers were cited as the trigger for raids at Swift & Co. meat processing operations in Hyrum; Greeley, Colo.; Grand Island, Neb.; Cactus, Texas; Marshalltown, Iowa; and Worthington, Minn.

After the responses to this week's mailings are gauged, Workforce Services will determine a time schedule for further notifications, Stewart said.

"For right now, this is sort of testing the waters, a first foray into attacking the problem," he said.

The letters note that while problems have been found, they are not notices of an official law enforcement investigation. Whether such cases are prosecuted is up to the state Attorney General's Office, Stewart said.

The letters urge parents who suspect their child's Social Security number is being misused to report their concerns directly to the A.G.'s office Web site, www.idtheft.utah.gov. The site provides a "DWS Notification" link and instructions on how to file a Social Security theft complaint.

Those without Internet access can call the A.G.'s office direct for assistance: 801-281-1267.