Hundreds of buildings -- from houses to strip malls -- could face the wrecking ball after California authorities unraveled a decade-long scam involving a pair of phony building engineers who used stolen software to craft bogus blueprints, officials told FoxNews.com.

Wilfrido Rodriguez and Ruben Gutierrez, allegedly posing as licensed professionals and using stolen software, drew up engineering and architectural plans for homes, apartments, commercial properties and strip malls in at least 56 Southern California cities beginning in 2003, according to police. Neither had the training, expertise or credentials to vouch for the safety of the building plans, and authorities are only now grasping the scope of the problem.

“There has never been a case involving alleged engineering fraud of this magnitude,” Detective Rod Barton, of the Los Angeles County Sheriff’s Department’s Fraud and Cyber Crimes Bureau, told FoxNews.com. “Because this involves fraud related to structural engineering, we just don’t know if the houses are safe, unsafe or suitable for habitation.”

“There has never been a case involving alleged engineering fraud of this magnitude.” — Det. Rod Barton, of the Los Angeles County Sheriff’s Department

The pair duped architects, builders and homeowners into believing they knew what they were doing, Barton said. Now, authorities are tasked with reviewing every building the pair worked on and determining if they are structurally sound, an issue made all the more urgent given the frequency of earthquakes in California.

“A significant concern is foundations,” said Panos Prevedouros, a professor and chair of Civil and Environmental Engineering at the University of Hawaii-Manoa. “Experienced drafters can work out safe designs for small masonry structures, but proper foundation design and specialized structural components required detailed engineering analysis.”

Before embarking on their alleged scam, the pair worked for the Rolling Hills Estates-based Palos Verdes Engineering Company. The company, which declined to comment for this story, told authorities it uncovered the alleged engineering fraud after a customer complained about an offer made by the men in April 2014.

Since that time, Barton and his bureau have been tracking down projects that involved the pair, and have been stunned and horrified at the number of buildings involved.

“Up until then, nobody had any knowledge that this fraud was occurring,” Barton told FoxNews.com. “We visited 56 cities from San Bernardino and Riverside to Ventura County. Our nexus were the initial files Palos Verdes Engineering identified, and then we segued into other projects. It was a lot of groundwork.”

Law enforcement authorities are working the Board of Professional Engineers, Land Surveyors and Geologists to determine the scope and risk posed by the alleged fraud.

“Evidence thus far uncovered leads us to believe there were hundreds of projects built on their fraudulent structural engineering,” said Tiffany Criswell, the board’s enforcement manager. “Evidence leads us to believe there are additional properties we have yet to identify.”

One challenge for law enforcement is that many local governments only keep design and engineering plans on file for six months.

“The Los Angeles County Sheriff’s Department sent contact letters to homeowners, developers, and architectural designers whose properties have been identified as possibly being associated with fraudulent structural engineering,” Barton said. “Investigators believe additional properties associated with structural engineering fraud may exist, but have not yet been identified.”

The men have not been charged and are cooperating with the sheriffs’ detectives. While sheriffs didn’t say how much the men allegedly profited on the deal, they likely made at least $2,000 to $3,000 per project on potentially several hundred projects over 11 years, according to industry insiders.

The LA sheriff’s white collar crime division will consider the case and whether to charge the men with a variety of crimes including civil engineering fraud, grand theft, theft of company identity, and forgery, LA sheriffs’ detectives said.

Palos Verdes Engineering Company had no business relations with the men between 2003 and 2014, during the time the alleged fraud occurred, Barton said. The men allegedly stole software from the company, which was used to produce fraudulent engineering plans bearing its company name and logo, Barton said.

“Palos Verdes Engineering Company’s civil engineer seal and forged signature was also used on structural engineering records to make the plans appear authentic, and as if they had been reviewed and approved by a licensed professional civil engineer.”

Legitimate professional engineers must have a degree in civil engineering, pass several grueling exams and obtain five years of experience before they can sign off on design documents for implementation.

On the architectural side, the value of architectural licensure is “immeasurable,” said Matt Tinder, spokesperson for The American Institute of Architects, in Washington, DC.

“Without it, the entire built environment could serve as a public safety hazard,” Tinder said.

While there have been no glaring design flaws brought to the sheriff’s attention, there could be a risk to the public, which could be heightened by a natural disaster such as an earthquake. The sheriff’s department is advising homeowners who worked with Rodriguez and Gutierrez to contract the services of a civil engineer to go through the plans, examine their residence and determine if they are safe.

“We want to make sure people are safe,” Barton said. “There is a reason all these requirements are in place. When the whole procedure is circumvented, something bad can happen.”