To a seamstress living in poverty in central Vietnam, the radio ad sounded enticing: A government manpower company was looking for workers to sew clothes in a U.S. factory for a salary many times what she was used to earning. With income from the job, Quang Thi Vo hoped to improve the lot of her family -- living in a small house without running water or indoor plumbing -- and send her two children to college.

What followed, however, was a 20-month nightmare in a steamy sweatshop and prison-like barracks on American Samoa, a U.S. territory in the South Pacific. According to federal officials, the factory's South Korean owner held more than 200 workers, mostly Vietnamese, in virtual slavery, illegally confining them and paying them only a fraction of what they were owed. In what the officials described as the most extensive such case ever prosecuted, the factory boss deprived workers of food, ordered them beaten by guards and arranged to have them deported if they complained.

"Because my family was so poor, I thought I would go to American Samoa to make some money and support them," said Vo, who left behind a husband and two children in Quang Binh province in what was once North Vietnam. "But when I got there, I was so disappointed." Yet she couldn't leave, she said, because then she would have been unable to repay the $5,000 she borrowed to land the job.

Today, Vo, 33, is one of nearly 200 Vietnamese women who have settled in the United States -- 13 of them in Northern Virginia -- with the help of Boat People SOS, an organization in Falls Church that has aided thousands of refugees from Vietnam over the past two decades.

The group, headquartered in a bank building near the Eden Center -- the heart of the Northern Virginia's Vietnamese community -- began by helping refugees who escaped Vietnam by boat, hence its name. Now it is turning its attention to another group in need: victims of an often vicious international trade in human beings.

With the help of a Justice Department grant, Boat People SOS plans to expand an effort that began with the American Samoa case. The social service agency was among a dozen recipients of grants totaling $9.5 million to help victims of human trafficking, the department announced last month.

The Justice Department estimates that 50,000 women and children are trafficked into the United States every year. Boat People SOS is to receive nearly $1.9 million over three years and will offer such services as emergency medical care and mental health counseling to victims who end up in the Washington area.

According to Nguyen Dinh Thang, Boat People SOS's director, victims include not only sweatshop laborers such as Vo, but women and children forced into the sex trade and domestic servants held as virtual slaves by foreign diplomats and employees of international organizations such as the World Bank and International Monetary Fund.

"We know that this area is a hot spot for human trafficking," Thang said.

Vo and other former workers at the Daewoosa garment factory in American Samoa were encouraged by the Feb. 21 conviction of owner Kil Soo Lee, 52, on federal charges of involuntary servitude, extortion and money laundering. Lee was convicted in U.S. District Court in Hawaii after a four-month trial in what Ralph F. Boyd Jr., assistant attorney general for civil rights, called "the largest human trafficking case ever investigated by the FBI and prosecuted by the Justice Department."

The exploitation of the Vietnamese and Chinese workers "amounted to nothing less than modern-day slavery," he said. Earlier, two Samoans pleaded guilty in the case. All three are to be sentenced in June.

Thang called the verdict a "moral victory," but noted that Vo and the other workers still are waiting to be compensated for suffering and unpaid wages. In a civil judgment by the High Court of American Samoa last year, Daewoosa and two Vietnamese government-owned manpower agencies were ordered to pay the workers $3.5 million, but they have yet to collect. Since the factory has folded, and Lee remains jailed in Hawaii pending sentencing, Thang said, Boat People SOS is trying to extract payment from the Vietnamese government, possibly through the seizure of property in the United States.

Vo said she is owed about $10,300 under the judgment. While waiting for that settlement, the shy and soft-spoken former seamstress works at a Vietnamese bakery at the Eden Center, earning $800 a month while also attending English classes at a nearby community center for immigrants. As a witness in the criminal case against Lee, she has applied for a special "T" visa, which would allow her to remain in the United States as a nonimmigrant and eventually apply for permanent residence. She shares an apartment near Seven Corners with two of her former co-workers.

Although the Daewoosa workers hail from the north, Thang said, they have been welcomed by the local Vietnamese community, which is made up largely of people who fled the communist takeover of South Vietnam.

Vo said her odyssey began in May 1999 when she paid a $4,000 commission, plus $1,000 in expenses, to land a job that she was promised would pay her $408 a month plus overtime, possibly totaling $1,000 a month. The company, Daewoosa Samoa Ltd., also agreed to pay for her food and lodging.

It seemed a fortune for someone who had been earning about $20 a month sewing clothes at home to supplement the meager income of her husband, a truck driver. The family had enough to eat, Vo said, but otherwise was barely scraping by, with only a bicycle for transportation.

Upon arrival in American Samoa, she and the other Vietnamese were shocked to find themselves in a literal sweatshop, a factory that was crowded, hot and steamy, sometimes reaching 140 degrees on the factory floor. Vo was shown to a dormitory room crammed with bunk beds for three dozen other workers, some sleeping two to a bed. Food consisted mostly of a weak broth of potatoes and cabbage, leading many workers to complain that they were practically starving.

When Daewoosa had orders to fill, the workers toiled up to 14 hours a day, according to court records, to produce clothing for J.C. Penney, Kohl's, Target and other U.S. retailers. But at other times, they remained idle for long periods, receiving no pay in violation of their contracts. For her 20 months of employment, Vo said she received only $2,500 from Lee, an average of $125 a month.

Rising tensions between the workers and Daewoosa management culminated in a melee on the factory floor in November 2000 in which workers were beaten by Samoan guards wielding PVC pipes as clubs, Vo said in an interview and court documents.

One Vietnamese woman lost an eye when she was struck with one of the pipes. About three weeks later, the factory closed.

Vo came to the United States in March 2001 to be a witness in the case against Lee, testifying at his trial last December. Once she receives her "T" visa, she hopes to bring her husband and two children -- a 13-year-old daughter and 6-year-old son -- to Northern Virginia to join her.

"My husband and children really miss me," she said, "and I miss them, too."

Nguyen Dinh Thang, left, and Jean Beruggeman, both of Boat People SOS in Falls Church, flank Quang Thi Vo, who spent 20 months in a sweatshop in American Samoa after being lured from Vietnam by promises of good wages.