South Korean lawmakers are concerned about the number of Korean women who have come to the United States to work as prostitutes since the Korea-US Visa Waiver Program began in 2008.

In the past five years, hundreds of Korean prostitutes have been arrested in the Mid-Atlantic states  of the U.S., including New York, and  lawmakers are urging  the Korean government to come up with solutions.

Since 2007, more than 200 Koreans have been caught for their involvement in the sex trade on the east coast, according to data released on Sept. 19 by Rep. Sun-young Park of the Liberty Forward Party in Korea. The illegal massage parlors and spas where prostitutes provided sexual services were mainly found in New York, New Jersey and Virginia

“As Koreans can enter the United States more easily than ever with the visa waiver program from 2008, the number of Koreans involved in the sex trade in the U.S. has rapidly increased,” Rep. Park said. “Government-level effort is urgently needed.”

Recently, the FBI apprehended a woman, who had entered the country to work as a nurse, and charged her with procuring prostitutes for clients in New York City. She is now behind bars. According to the Korean Consulate General in New York, the woman is also suspected of human trafficking. Some prostitutes hired by the woman filed a complaint against her for not paying them a salary.

The trend extends to the west coast as well. Not long ago, four Korean women in California were arrested for selling sex after opening a massage parlor. In Alaska, a Korean couple was caught  operating a brothel exclusively for senior citizens.