The regulars at the Park Place Tavern weren't surprised when police raided what is being described as an Asian brothel in a small house across their shared driveway.

But they were surprised when news reports linked the now-closed Tokyo Spa (search) and two other health clubs in the area to what police say is an international prostitution ring that smuggled Asian women into the United States and made them sex slaves.

"We joked about it here all the time," said Sandy Maloney, who lives in an apartment complex out back.

Maloney said she watched as older men driving expensive out-of-state sport utility vehicles visited the Tokyo Spa at all hours.

Experts in sexual slavery say the Vermont case fits the pattern of a problem that is reaching into the smallest corners of the country.

"Modern-day slavery is the fastest growing criminal industry in the world," said Derek Ellerman, co-executive director of the Washington-based Polaris Project (search), a grass-roots anti-trafficking organization.

"They have done a very good job of spreading into suburban and even rural areas," Ellerman said. "It's a market-driven criminal industry. Wherever there is demand for commercial sex the traffickers will spread to those areas."

There's an eviction notice on the door of the light gray two-story clapboard house that operated as the Tokyo Spa for about a year. The city of Burlington is moving to evict the tenants from another of the spas. At the third, the building owner insists all the activity inside was legal.

Police, though, contend the clubs were offering sexual services along with massages. During the raids earlier this month, authorities arrested eight women — five Korean and three Chinese — on federal immigration charges.

All except two have been released, said Essex police Lt. Gary L. Taylor. No state criminal charges have been filed.

Taylor refused to discuss the ongoing investigation but knew of no other organized prostitution in Vermont's history.

"It's the first time I am aware of," Taylor said.

In court documents, police say the women who worked at the spas never left. Even groceries were brought to the house.

One Korean woman told investigators she had been smuggled into the United States and had only recently arrived at the Tokyo Spa.

Court documents filed by police to get search warrants for the three businesses outline what authorities say could be a link to international organized crime and sexual slavery. Similar operations, according to the papers, are being investigated by federal authorities in New York City, New Jersey and Maine.

"The way these massage parlors or spas or health clubs work, they are really fronts for prostitution," said Donna Hughes of the University of Rhode Island.

Hughes, who has studied international sex trafficking for 15 years, said many of the women have been smuggled into the United States and are being held "by some sort of forced fraud or coercion."

Typically, sex rings offer to bring women into the United States for a fee. Once in the United States, the women are forced to repay the cost of their passage by working as prostitutes.

The women will give most of the money they make to the brothel owner. They are charged for rent and expenses. They can be fined for rule infractions, Hughes said.

"There are all sorts of things they do to prevent these women from getting out," Hughes said. "That may mean these women have been enslaved for 20 years."

The women are then rotated between the brothels as part of a network that has, in some cases, operated nationwide.

Asian women aren't the only ones enslaved. The Vermont case appears to be a Korean network, Ellerman said. And traffickers bring women to the United States from around the world.

Law enforcement has a new tool for fighting the international trafficking. The federal Victims of Trafficking and Violence Prevention Act (search) of 2000 defines women who were forced into prostitution as victims rather than criminals, Hughes said. The statute also offers a range of social benefits and services, including a visa to stay in the United States, for victims who agree to cooperate with the authorities.

Ellerman said the effort to get the public to recognize sexual slavery as a problem is still in its infancy.

"It's much like domestic violence was 30 years ago. It took years to [become] mainstream," Ellerman said. "We're at that beginning stage right now."