MONROE, N.C. -- Two women arrested in a prostitution investigation at a North Carolina massage parlor may have been sex slaves illegally brought to the United States, police said.

Son Jarkowsky, owner of the parlor in Monroe, was charged Saturday with trafficking people and allowing a business to be used for prostitution. Police said she violated a total of 33 city ordinances.

The Island Day Spa opened in 2007 and police said it catered to male customers, but that females who sought massages were ignored.

Police said the business advertised on the Internet and customers came from hundreds of miles away. A listing Eyewitness News found on the Craigslist Web site under “Erotic Services” reads, “Come relax at the Island.” The phone number listed is the same number as the Island Day Spa’s.

Two employees also were arrested, one on a charge of an attempted crime against nature and the other on two counts of indecent exposure. Investigators said Monday they believe the women were being held against their will and described them as victims, but they said the women still committed crimes so it’s up to the district attorney to decide what happens next. The district attorney did not return calls from Eyewitness News on Monday.

Sgt. T.J. Goforth said the women didn't speak each other's language and slept on mattresses in the parlor. He said it wasn't clear if they ever left the business

A worker in the strip mall said, “I would never see them leave, just Sonny. She'd be the one to leave. She would come in and out, but not the two girls.”

Goforth also said authorities were seeking counseling for the employees.

The four-month investigation showed one woman was from China and another was from South Korea. The probe began when officers received a tip in April and sent undercover officers into the business.

Workers in nearby businesses said the arrests didn’t come as a surprise. One woman said at first she was excited about the prospect of a day spa nearby, but then she began to suspect something strange was going on.

“We thought, ‘Hmmm, that's kind of unusual.’ We never saw any women go in,” she said.

She said it was only businessmen visiting, and they would park away from the spa’s entrance, hurry in and hurry out. She said her curiosity turned to suspicion when the spa’s owner put up security cameras pointing away from the business.

All three women charged have bonded out of jail.

Monroe police said they expect federal agencies to get involved at some point.

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