HARRISON TOWNSHIP (WWJ) – Four women are facing prostitution charges in connection with alleged activities at a Harrison Township massage parlor.

The employees of Sun Chinese Spa, on Jefferson Ave., were arrested after a two month investigation that began when authorities received an anonymous tip that workers were offering sex to clients and ads were posted on a well-known website.

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The spa was put under surveillance and undercover detectives visited the business. On Jan. 14 a search warrant was executed, business records were seized and the spa was shut down.

According to Macomb County Sheriff’s officials, at least one of the suspects is in the U.S. illegally.

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Taken into custody were Meijuan Yu, 49 (immigration status unknown); Suhua Mei, 44 (in the U.S. illegally); Hongmei Qu, 26 (immigration status unknown); Xiaoying Yu, 51 (immigration status unknown). All reside in Harrison Township.

A fifth woman was arrested but later released when it was learned she’d just arrived in Michigan the same day the bust took place, officials said.

Yu, Yu, Mei and Qu were arraigned Tuesday on charges of maintaining a house of prostitution, accosting and soliciting and using a computer to commit a crime.

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Each remains held in the Macomb County Jail on a $20,000 bond pending a hearing set for Wednesday, Jan. 27.