The Sudbury Police Department arrested an employee of Oriental Bodywork and Reflexology Wednesday night after investigating a report of possible illegal activity at the 345 Boston Post Road business.
According to Lt. Scott Nix, an investigation was initiated in Unit D of the building's first floor as to the validity of the activity in an undercover operation on Wednesday.
The result of the operation was the arrest of Lian Hong Zhao, 48, of 7 Temple St., Apt. 435, Cambridge. She is charged with sexual conduct for a fee.
Zhao was booked Wednesday night and later bailed out on personal recognizance.
Nix said the department contacted the state agency that licenses such venues but had not heard back as of Thursday morning.
Her arraignment was scheduled for Thursday at Framingham District Court.
"The matter remains under investigation and additional evidence was seized at the time of the arrest," Nix said in a statement.
Detectives from Maynard and Hudson assisted with surveillance.