WASHINGTON -- Federal agents said they've busted a ring involved with human trafficking.

Authorities have 31 people in custody and more than 70 suspected Korean sex slaves were freed. Investigators said the suspects smuggled Korean women through Canada and Mexico. To help pay off their smuggling fee, the women were forced to work in brothels in seven states -- including Maryland -- and the District.

Julie L. Myers, assistant secretary for U.S. Immigration and Customs Enforcement, said the victims who were working in brothels throughout the Northeast were being interviewed by ICE agents at secret, non-detention locations where they were receiving health care, clothing, food and other services as they were being questioned. She said it was disheartening to hear agents describe stories "of women who were promised a better life and instead held as sex slaves." Yet, she said, she was encouraged to know "these same women had been rescued and freed from their shadowy existence and that we could help bring to justice those criminals who enslaved them."

The suspects were arrested Tuesday and face charges including conspiracy to engage in human trafficking, conspiracy to engage in interstate transportation of women for the purpose of prostitution, conspiracy to transport illegal aliens, transportation of illegal aliens and conspiracy to operate an unlicensed money-transmitting business. If convicted, those charged faced maximum sentences of five to 10 years.

In Northwest, five spas were raided on K and 10th streets and Vermont, Connecticut and Wisconsin avenues.

According to court documents, the investigation began in May 2005 when a Korean couple accused of operating a chain of brothels in New York attempted to bribe an undercover New York City police detective. The couple and two New York police officers accused of accepting bribes were arrested and charged with public corruption offenses in March.

Myers said the United States was seeking to break the backs of the human trafficking rings by increasing the number of investigations of smugglers and traffickers and targeting the financial proceeds of the criminal organizations.

"Some of these criminals look upon people as cargo, just something that must be moved," she said. "But we know that the victims of trafficking and smuggling are not cargo. They are human beings who often have been mentally and physically broken down in every way possible to achieve a mental state in which they can no longer fight against their captors and try to escape."

She said it might take weeks to build enough trust with wary victims to get them to speak to investigators, and she acknowledged that some of the 70 suspected victims might turn out to have known the risks of the brothel trade and chose to work in it anyway.

U.S. Attorney Michael Garcia said the smuggling organization relied on recruiters who went to Korea and found young women eager to live in the United States. The recruiters then charged the women tens of thousands of dollars to provide false documentation to enter the country or to smuggle them in, he said.

Once in the United States, the women were placed in brothels along the eastern seaboard, unable to leave the business until their debt was paid, he said. Identity and travel documents were seized from the women, threats were made that they would be turned over to authorities or that family members would be harmed in Korea if they tried to leave, Garcia said.

"Raids on these locations show that this exploitation is not a back alley business. It happens on Main Street in Stamford, Conn. It happens in residential neighborhoods of our nation's capitol and it happens in the West 20s in New York City, not far from here," Garcia said at a news conference at FBI headquarters in lower Manhattan.

He added: "Human traffickers profit by turning dreams into nightmares. These women sought a better life in America and found instead forced prostitution and misery."

The suspects include suspected brothel owners and managers, people involved in unlicensed money-transmitting businesses, and people accused of assisting the organization.

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