GREENSBORO, North Carolina (AP) -- About 3.5 years after the Sept. 11 attacks, more than two dozen alleged illegal aliens - including four from so-called countries of special interest for terrorist activity - got jobs maintaining commercial jetliners in North Carolina.
They passed through criminal background checks and Social Security screenings. Six held the Federal Aviation Administration's top mechanical certification, allowing them to clear airplanes to return to service.
Scott Vines - who just learned that the quiet, unassuming Sudanese man who lived in the apartment below him was arrested with 26 others - would like to know how.
''It's one thing to have an illegal alien working soybean fields or tobacco,'' he says. ''But to have somebody working on aircraft ... that is scary.''
Just how frightened people should be of last month's roundup of 27 workers at TIMCO Aviation Services' Greensboro facility is open to debate. Some in the industry say it shows the security loopholes in the growing outsourcing of aircraft repairs.
As much as half of the servicing of the nation's airliners is now outsourced to third-party vendors whose mechanics are not required to be certified, or to have the extensive FBI background checks done on in-house airline mechanics.
''Any time we have individuals working at critical infrastructure locations like airports that are not who they say they are and may be utilizing fraudulent documents, it does pose a potential security threat,'' says Dean Boyd, a spokesman for the U.S. Immigration and Customs Enforcement Agency.
''It exposes a vulnerability, and it also shows that a potential terrorist or criminal could do the same thing.''
On March 8, federal agents swept down upon TIMCO's sprawling facility amid the rolling hills surrounding Piedmont Triad International Airport, where a sign on one hangar reads ''$AFETY PAY$.''
The raid was part of Operation Tarmac, a 3-year-old, multi-agency effort that has resulted in 1,120 arrests and 775 indictments at 200 airports. Previous sweeps have netted janitors, foodservice employees and even pilots. But never before had so many aircraft mechanics been picked up at one time.
Most of those arrested came from Central and South America, countries such as Chile, Peru and Venezuela. But two each hailed from Sudan and the Philippines - countries on a Department of Homeland Security watch list for potential terrorist links.
But TIMCO President Gil West says this is strictly an immigration issue and any suggestion of terrorism is exaggerated. The arrested workers, most of whom were outside subcontractors, were all qualified to do the tasks they were assigned and were under the supervision of U.S. citizens federally certified in their fields.
TIMCO officials also noted that the workers with the top certification were working in the sheet metal and seating departments, not on engine systems or other more sensitive areas.
''There isn't a security or safety issue associated with it,'' says West, whose company does work for United Airlines and other passenger and cargo carriers.
Many of those picked up at TIMCO had allegedly used fake North Carolina driver's licenses to obtain work. According to an affidavit, one Peruvian man told a federal agent he paid $50 (euro39) for a fake Social Security card at a Miami soccer park.
Six of those arrested had federal airframe and powerplant certificates, the top certification for aircraft mechanics, says FAA spokeswoman Kathleen Bergen.
Bergen says all six passed the tests for that certification, but the agency is looking into whether the men used fraudulent documents to qualify for the tests.
So far, agents have found no link between any of the men and terrorist activities. But Boyd says any of these men could have been subject to blackmail and could have posed a security threat.
One of 27 people affiliated with TIMCO was sentenced to time already served.
FAA is investigating how five mechanics working for TIMCO, who were arrested two weeks ago on immigration charges, received their A&P certificates.
The Federal Aviation Administration is investigating how five people arrested on immigration charges qualified for licensing tests for the FAA's high-level repair licenses.