A legislative audit shows Utah's "relatively lenient requirements" for obtaining a driver's license are being abused by illegal aliens — a problem already under federal investigation that Senate leaders said Wednesday they plan to fix.

Their solution is a bill creating a new category of driver's license that could not legally be used for identification purposes — a "driving privilege card" that could not, for example, be used to board an airplane.

The audit was privately requested by Senate President John Valentine, R-Orem, who said federal authorities are already investigating several Utah cities from which "contractors" are issuing several drivers' licenses. For example, the address of one Salt Lake City apartment was linked to 65 licenses issued over 15 months.

Utah Attorney General Mark Shurtleff said his office will join the effort. "Obviously we are very concerned about any kind of voter or driver's license fraud," Shurtleff said. "We'll aggressively pursue an investigation into the allegations."

Dave Ward, Immigration and Customs Enforcement resident agent in charge for central Utah, said a preliminary investigation has revealed a widespread problem.

"I've read the audit, and it's much larger," Ward said. "We're trying to figure out how big this operation is and how our homeland security is being compromised by this."

Valentine said when he received the audit, he "recognized we had a problem with the way Utah drivers' licenses are issued. We have to respond to that problem for the protection of our citizens."

More than 58,000 drivers' licenses and 37,000 personal identification cards have been issued by the state to people who appear to be undocumented aliens, according to the audit.

Some 383 of them also registered to vote, the audit found, and 14 — who may or may not have been citizens — actually cast ballots in an election.

An examination of a sample of 135 of the registered voters showed five were naturalized citizens who were eligible to vote. The rest were likely not eligible to vote, including 20 labeled deportable.

The findings raise concerns that Utah is being "used as a portal for undocumented aliens living out of the state" to get drivers' licenses, Legislative Auditor General John Schaff noted in his 3 1/2-page letter to the Senate president.

Ward said the auditor's office asked him to verify names thought to be illegal aliens who had fraudulently registered to vote. He is also sorting through a list from the Department of Public Safety of single addresses used for multiple licenses. Many names appear on both lists, he said.

"If in fact it's true, we've got a serious problem," Ward said. "I've got a couple thousand names. . . . I am going to be checking into every single one. So far, 90 percent are illegal aliens."