CENTRAL ISLIP — A millionaire couple who brought two Indonesian women to America to work for them as housekeepers inside their Long Island mansion were convicted today of what prosecutors called a case of “modern-day slavery.”

Varsha Sabhnani collapsed into the chest of her husband, Mahender Sabhnani, after a jury found them guilty of all charges in a 12-count federal indictment that included forced labor, conspiracy, involuntary servitude, and harboring aliens.

Moments later, one of their daughters fainted while sitting in the front row in the courtroom gallery. Soon after, her mother went to comfort her and she too fainted. Both women were taken to an area hospital, prompting the judge to postpone the remaining court proceedings until tomorrow. Their conditions were not immediately known.

The verdict brought an end to a trial that portrayed the Sabhnanis’s elegant mansion as a house of horrors for the two victims, who came to America for a better life but ended up making pennies an hour under horrendous conditions.

The victims said they were beaten with brooms and umbrellas, slashed with knives, forced to climb stairs, and take freezing cold showers as punishment for various misdeeds. One victim was forced to eat dozens of chili peppers against her will, and then was forced to eat her own vomit when she couldn’t keep the peppers down, prosecutors said.

The defense contended the two women concocted the story as a way of escaping the house for more lucrative opportunities. They also argued the housekeepers practiced witchcraft and may have abused themselves as part of an Indonesian self-mutilation ritual.

The trial also provided a glimpse into the growing problem in America of domestic workers being exploited in slave-like conditions. Experts hoped that the verdict would have a lasting legacy.

“This certainly does send a message that people can’t do this,” a sociology professor at Hunter College, Nancy Foner, said. “This is a lesson; I hope this verdict will make people frightened.”

Although the couple could face as much as 40 years in prison, attorneys predicted the punishment would be considerably less. No sentencing date was set for the Sabhnanis, who run a global perfume business.

Defense attorneys said they would appeal. Lawyer Stephen Scaring said another of the Sabhnanis’s daughters, Tina, was in disbelief; the couple has three daughters and a teenage son. “We never did anything to anybody, how could this happen to us in America?,” Tina Sabhnani told the defense lawyer.

Prosecutors refused to comment until court proceedings were completed.

Over six weeks of testimony that included the two Indonesian women testifying through an interpreter, prosecutors laid out evidence that pointed to what they called a case of “modern-day slavery.”

Assistant U.S. Attorney Mark Lesko said in closing arguments that the poorly educated women barely eked out a living in Indonesia and came to America to work as housekeepers for $100 or $150 a month — all of which was sent to their relatives back home. One of the women arrived in the Sabhnanis’s Muttontown home in 2002; the second came in 2005. Their passports and other travel documents were immediately confiscated by the Sabhnanis, the women testified.

Mr. Lesko said the maids were subjected to “punishment that escalated into a cruel form of torture” that ended last May when one of the women finally fled in the early morning hours of Mother’s Day. She wandered into a Dunkin’ Donuts, where employees called police.

The women said they were tortured and beaten for misdeeds that included sleeping late or stealing food from trash bins because they were poorly fed. Both women, known only as Samirah and Enung, also said they were forced to sleep on mats in the kitchen.

The women have been cared for during the investigation by Catholic Charities, and it unclear where they would go after the trial.

Although Varsha Sabhnani, 45, was identified as the primary culprit in inflicting punishment, Mr. Lesko said her 51-year-old husband was charged with the same crimes because he allowed the conduct to take place and benefited from the work the women performed in his home.

He also noted that because the Sabhnanis’s international perfume business is run out of an office adjacent to the home, Mahender Sabhnani was likely privy to the discipline being imposed by his wife.

“Ask yourself who is worse,” Mr. Lesko said. “The twisted soul who tortures maids or the man of the house who lets it happen?”

“This did not happen in the 1800s,” he said. “This happened in the 21st century. This happened in Muttontown, New York.”

The Sabhnanis spent nearly three months in jail following their arrest before a judge signed off on a bail package that required the couple to post $4.5 million and pay an estimated $10,000 a day for round-the-clock security monitoring while they were kept under house arrest.

Prosecutors had argued the Sabhnanis — he is from India, and she is from Indonesia, but both are naturalized American citizens — were a flight risk.