Three massage parlour operators have been charged in connection with ongoing investigations into human trafficking.
Police say the massage parlours were actually fronts for prostitution.
Late Thursday evening officers raided two massage parlours in Montreal and one in Dorval and arrested the women who ran the operations.
Li Wang, 53, Yi Zhang, 38, and Dong Bai, 39, were in court Friday and charged with keeping a common bawdy house.
One client was also arrested and will appear in court in February on charges of being in a den of iniquity.
The raids this week come a month after Marius Trifu Miclescu and half a dozen other people were charged with human trafficking and living off the avails of prostitution.
Police say Miclescu's gang brought Romanian women into Canada and forced them to work in erotic massage parlours, in some cases bringing entire families into the country.
One advocacy group that assists women in the sex trade said that they would like to ensure that women working in such parlours are not seen as criminals.
"We'd like the women to be decriminalized and get the help they need of being victims of prostitution or trafficking," said Eliane Legault-Roy of La Cles.
Montreal Mayor Denis Coderre said that the city is examining possible ways of limiting massage parlours that offer sexual services.
"A health centre is a health centre, it's not for that kind of thing," said Coderre.
