Officials in Canyon County, Idaho (search), say that illegal immigrants are costing their county millions of dollars in medical and welfare benefits — millions of dollars the county wants back from agricultural companies, officials say, that knowingly employed undocumented workers.

In an unprecedented move, Canyon County is suing several local businesses under the Federal Racketeer Influenced and Corrupt Organization Act.

"It's an organized, orchestrated invasion, economic invasion of the United States," said Canyon County commissioner Robert Vasquez. “They're costing the county money in medical indigency welfare cases, and also in crime and other statistical data that we've compiled"

The RICO Act was originally designed to target organized crime, and it has been used a number of times to accuse companies of conspiring to lower wages by hiring illegal immigrants. But the lawsuit filed by Canyon County in U.S. District Court in Boise takes the conspiracy theory to a whole new level.

The Idaho Farm Bureau (search) says companies in need of laborers often walk a fine line between proving worker eligibility and being accused of discrimination.

"They are limited in the way they can document whether or not an individual is legally in the United States," said Dennis Tanikuni of the Idaho Farm Bureau. But officials in Canyon County said that they aren't buying this explanation.

"When you need an excuse any excuse will do," said Vasquez.

In a statement, Swift and Company (search), one of four agribusinesses listed on the lawsuit, said the firm "will vigorously defend itself against these unfounded allegations."

Other local governments struggling with issues related to illegal immigration across the nation are likely to watch this court case closely. The case is expected to go to court in late October.

Click in the video box near the top of the story to watch a report by FOX News' Alicia Acuna.