The name Pablo Escobar might almost be synonymous with drug trafficking. But a man with a less familiar name emerged as the kingpin of a different -- though equally underground -- kind of operation.
"Pedro Castorena, he is equivalent to Pablo Escobar in the fraudulent document ring," said Marcy Forman, director of investigations for Immigration and Customs Enforcement (ICE).
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Last year's arrest of Castorena in Mexico uncovered one of the biggest counterfeit ID rings in the world, exposing the large-scale problem of document fraud.
Castorena ran counterfeiting franchises in 50 U.S. cities and 33 states, providing bogus IDs and documents to tens of thousands of illegal immigrants.
Forman's comparison to a drug trafficking organization didn't end with drawing a parallel between Castorena and Escobar. She described the vendors on city streets, looking for business, runners who transport information from the customers to those who make the documents to order.
"And then you have the document mills and the labs that make these counterfeit documents -- everything from social security cards to matricular cards to birth certificates to drivers' licenses," Forman continued. "And then you have the organization that actually manufactures and distributes throughout the United States and throughout the world. It's not just a domestic problem. It's a global problem as well."
The money the industry illegally pulls down is staggering. According to Forman, "[It's a] multimillion, potentially multibillion dollar operation."
Even before sharing in a percentage of those profits, Castorena's franchises had to pay a fee of up to $15,000 just to operate.
Undercover video shot by law enforcement shows those vendors sell the fake ids to willing buyers on street corners across the country.
"We're talking about millions of counterfeit documents that are being produced in this country," said Forman. "It's significant and it's almost at epidemic proportions. It's a national security risk."
Using Technology to Fight Technology
Fake drivers licenses, passports, social security cards, green cards -- almost undetectable to the naked eye.
At ICE's forensic document laboratory in northern Virginia, outside Washington, D.C., agents are using state of the art technology to examine what they say are increasingly sophisticated counterfeit IDs.
One of those forensic document examiners told ABC News the availability of advanced computer technology allows the counterfeiters to create convincing documents.
"The advent of the desk top technology -- scanners, printers, these sorts of things that are becoming more available -- they are higher quality and they are really producing high quality documents and in many cases very difficult to tell that alterations have been taking place or that documents are counterfeit in it of themselves," said Carolyn Bayer-Broring.
Forensic examiners use ultraviolet light beams and high-powered microscopes to try to keep up with the counterfeiters.
But the counterfeiters can be extremely creative, making fakes from scratch or from stolen authentic documents.
In one case, the counterfeiter bleached the ink off a passport, flawlessly replaced the picture, and typed in new identification information.
"To the naked eye you can't see that there's anything there," said Bayer-Broring. "But when you use the spot filter that's available to us, you are able to see that actually there was prior data that was on this document that has been rinsed off."
Many business owners, especially those in the agriculture and the construction trades, say they are at a loss to tell real IDs from fake ones, and as a result, have no way of knowing if they are hiring legal or illegal workers.
"If an applicant for a job comes in and brings you three valid forms of identification, they look real, they look valid to you, you can't go much beyond that without putting yourself at risk of discrimination," said National Association of Home Builders CEO Jerry Howard.
The problem, say government investigators, is that this black market industry has millions of customers, just waiting for the opportunity to buy their way into the system, even if it is illegal.