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Mexican guest workers are claiming that a landscaping company subjected them to constant surveillance, threats, forced labor, and human trafficking, according to a federal lawsuit filed in Nashville.

The suit claims managers with Vanderbilt Landscaping, LLC, subjected foreigners working under the nation's H-2B visa program to constant surveillance and threats.

A message left late on Thursday for Vanderbilt Landscaping managers was not immediately returned.

According to the lawsuit, workers arriving from Mexico had their passports and visas confiscated and were forced to live in company housing where they were under surveillance. Managers sometimes went armed and one told workers that if they left the camp without permission they would be turned over to immigration authorities, according to the suit, which seeks unspecified damages.

The workers, who mowed the medians of Tennessee highways and interstates and picked up trash, claim housing conditions were inhumane and working conditions were exploitative, the court papers indicated.The suit also claims Vanderbilt Landscaping subjected one worker to false imprisonment by forcing him to get on a bus back to Mexico after it was discovered he had complained about his treatment.

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The suit comes on the heels of proposed changes to the H-2B visa program, which allows companies to hire temporary foreign workers after certifying that they can find no American workers to take the jobs.

The complaints of the Tennessee workers echo those of several other groups of guest workers who have sued employers in recent years.

The New Orleans-based nonprofit Alliance of Guestworkers for Dignity is among those that have lobbied for changes to the H-2B program. The 14 plaintiffs, from the town of Ruiz in Nayarit, Mexico, are identified as members of that group.

One plaintiff, Hilario Razura Jimenez, has said he had to borrow money to come to work in the U.S. in 2009 and did not earn enough to pay back what he had borrowed, according to the suit. With interest, he owed the Mexican currency equivalent of about $2,000 from that trip when he came to the U.S. in May 2010. And he had to borrow even more money to make the second trip.

"Many people don't complain because they'll be fired, and they can't go back to Mexico because they owe lots of money in Mexico," he said.

The Alliance filed complaints in August against Vanderbilt Landscaping with the Tennessee Department of Transportation, the Labor Department and the Justice Department.

Labor's Wage and Hour Division has levied an $18,000 fine against Vanderbilt Landscaping for failing to properly recruit U.S. workers, placing foreign workers outside the area of intended employment and failing to accurately state the dates of temporary need, reasons for the temporary need and number of workers requested.

The company has appealed the fine.

The Tennessee Occupational Health and Safety Administration fined the company $4,700 for violations relating to equipment safety and crowded, unsafe company housing.

According to the lawsuit, the company had more than $2 million in state contracts with the Tennessee Department of Transportation since 2009.

Based on reporting by the Associated Press.

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