Nine Guatemalans were indicted for their roles in an alleged sex trafficking ring that lured young women to the United States with promises of good jobs and then forced them into prostitution, according to federal court records.

Four of the defendants pleaded not guilty in January to sex trafficking charges in the case. A superseding indictment, unsealed Thursday, includes more serious allegations that five of the 12 victims were minors.

According to the new 50-count indictment, the defendants at times sold Guatemalan women and girls to one another like slaves and allegedly brought the victims to witch doctors who threatened to put curses on them and their families if they ran away.

"These young women were enticed into coming to this country by promises of the American dream only to arrive and discover that what awaited was a nightmare," said Robert Schoch, a special agent in charge for U.S. Immigration and Customs Enforcement.

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A federal grand jury in Los Angeles returned the indictment against Gladys Vasquez Valenzuela, 36; her sisters, Mirna Jeanneth, 26, and Albertina, 49; and Albertina's daughter, Maria Vicente de los Angeles, 28.

The four face charges of sex trafficking of minors; sex trafficking by force, fraud or coercion; violating federal laws prohibiting interstate or foreign transport of minors for prostitution; and importing and harboring undocumented immigrants and harboring them for prostitution.

Five others also were charged in the indictment for their roles in the scheme, including guarding the women to prevent them from escaping, threatening their families in Guatemala, and beating and forcing the women to work, authorities said.

Four of the female defendants were arrested in December during raids in Los Angeles. One additional suspect, Flor Morales Sanchez, 33, was arrested Thursday. Six defendants remain in custody without bond. Another, Maribel Rodriguez Vasquez, is a fugitive.

A lawyer representing Luis Vicente Vasquez, 31, who faces counts of bringing women into the country illegally for prostitution, denies his client did anything wrong.

"We are going to court on this," attorney Philip Deitch said.

Attorney Errol Stambler, who represents Mirna Jeanneth Vasquez, said his client was a victim, not a trafficker. He said his own investigation revealed she had been forced into prostitution to repay smugglers who brought her to the U.S, and that her pimp forced her to house teenage prostitutes.

Messages left with two other attorneys representing defendants were not immediately returned.

The investigation began last year when two victims escaped with the help of a male customer and contacted authorities, according to the U.S. attorney's office.

Two other victims were rescued by investigators in November. Ten women at the locations raided also were believed to have been working as prostitutes.

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