The case against a Mississippi shipbuilder continues to mount with a new round of lawsuits accusing the company of engaging in human trafficking.

Last week, plaintiffs filed five lawsuits in Mississippi and Texas federal courts accusing Signal International LLC and its recruiting firms and brokers of "trafficking 500 Indian guest workers to the United States and forcing them to work under barbaric conditions," wrote the Southern Poverty Law Center—which filed the suits—on its website.

The most recent legal filings follow 83 federal H2B guest workers that sued Signal in federal court in May 2013. In 2008, 12 peopled sued the company. Together, the suits charge that Signal and its affiliate "defrauded guest workers out of millions of dollars in exorbitant recruitment fees" and falsely promised help in applying for and obtaining permanent U.S. residence.

The lawsuit states that Signal required each worker to pay as much as $25,000 to work in Signal's shipyards, located in Pascagoula and Orange, Texas. There, the suit claims, the workers had to live in "overcrowded, unsanitary and racially segregated labor camps."

When contacted this morning, a Signal representative said the company is not commenting on the allegations in the suits and referred this reporter to a statement on the company's website.

In the statement, Signal characterizes the lawsuits as representative of the SPLC's "agenda to cripple companies during labor shortages who attempt to legally employ workers through the H2B program."

"I am astounded at this abuse of the legal system. These are the same exaggerated claims that have been exposed as false allegations by a Federal Court Judge well over a year and a half ago. Signal made every attempt to bring these H2B workers into the Signal family of employees and treated them with dignity and respect, just as we treat each and every Signal employee," stated Richard Marler, Signal's chief executive officer, in the release.

In January 2012, Louisiana U.S. District Judge Jay C. Zainey declined to allow plaintiffs to pursue the case as a class-action lawsuit, writing in his order:

"The plaintiff class as a whole did not labor under any specific vulnerabilities when they decided to join the green-card program. That's not to say that they were not the victims of fraud, but (p)laintiffs are not a class of children or mentally challenged persons. The plaintiffs were adult men, some of whom had worked overseas before and some of whom were well-educated and savvy."

Plaintiffs are seeking damages and injunctive relief.