Twelve people were held by police following a raid on a spa in Nonthaburi on Tuesday.
The raid happened after authorities learned that the spa was offering sex services to customers.
"We also found that [the spa's managers] procured female sex workers, including some who were under 18, for its customers," police said, adding nine girls under the age of 18 were rescued during the raid.
He said the spa, which opened in June last year, didn't have a licence and was simply a front for prostitution.
As such, those who were found to be involved in the operation will face charges of child prostitution.
Police had received a tip that the spa was known to recruit attractive female workers through social media.
