SACRAMENTO, Calif. (AP/CBS13) — A Shasta County couple pleaded guilty Tuesday to forcing a Guatemalan relative and her two daughters to work long hours under poor conditions while keeping the girls out of school with threats that they would be deported.

Nery Martinez Vasquez and his wife, Maura Martinez, both age 53 and both of Shasta Lake, near Redding, pleaded guilty to conspiracy to commit forced labor.

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Both are naturalized U.S. citizens originally from Guatemala who promised their relative a “better life” if she came to America in September 2016, federal prosecutors said.

Instead, they forced the family members to overstay their visas and work long hours for little to no pay at their restaurant, called Latino’s, and at their Redding Carpet Cleaning & Janitorial Services, which served area businesses including multiple car dealerships.

“This case highlights how the dream of coming to the United States to begin a new, promising life can become a nightmare,” Sean Ragan, special agent in charge of the FBI’s Sacramento field office, said in a statement. The three worked in public view, he said, “yet were imprisoned by fear and the lies they had been told by their exploiters.”

As part of the plea agreement, prosecutors dropped charges filed in June alleging that in 1997 the couple conspired to kidnap a 13-year-old girl from her Las Vegas home, then held her against her will for nearly two years while Martinez Vasquez repeatedly raped and sexually molested the girl.

The forced labor conviction carries a sentence of up to 20 years in federal prison, but prosecutors also agreed to recommend a sentence of 6 1/2 years, said Sacramento area attorney Mark Reichel.

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“We were able to make an agreement that everyone could live with,” Reichel said. ”Going to trial in federal court is always an extreme gamble.”

Prosecutors said the couple told the woman and her daughters that they couldn’t leave until they paid a fictitious debt in full. They threatened to have them arrested for overstaying their visas and told the daughters they couldn’t go to school because they would be deported.

Instead, the girls worked for the couple’s businesses until February 2018, where Martinez Vasquez would sometimes hit them with a stick when he was angry, prosecutors said.

They and their mother were forced to live in what prosecutors described as “dilapidated, unheated trailer with no running water.”

Prosecutors did not disclose the girls’ ages, nor would they give the family’s current circumstances.

The couple agreed to pay the family and other victims $300,000 in restitution as part of their plea agreement.

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“These defendants used the promise of America to lure the victim and her children to the United States in search of a better life, only to turn around and use that hope to exploit their dreams under cruel conditions,” said Assistant Attorney General Kristen Clarke for the Justice Department’s Civil Rights Division. “There is no place for such cruel conduct in our society, and the Department of Justice remains committed to eradicating human trafficking.”