Around 20 people have filed a complaint with the Crime Suppression Division (CSD), alleging they were duped into buying bogus discount vouchers for hotels and resorts.
The complainants, led by a Mahidol University music teacher Ngamta Nanthakhwang, went to the CSD Thursday to seek action against Chatchamon Janta, 38, a contracted employee working for the Department of Science Service's (DSS) cooperative.
They claimed they were conned into buying fake hotel vouchers valued at more than 10 million baht, police said.
About 200 people are believed to have bought the vouchers.
Ms Ngamta told police she met Ms Chatchamon through a friend and she had assured her the vouchers were good for getting a 50-70% discount for stays at five-star hotels. She said she trusted Ms Chatchamon as she worked for the cooperative so decided to take part.
Ms Chatchamon often mentioned her work at the DSS's cooperative to make herself appear more trustworthy, and she believed her, Ms Ngamta said.
She said first bought the vouchers a year ago and found they were in fact redeemable for a discount, so she told friends about the discounts and they also bought vouchers from Ms Chatchamon, widening the circle of potential victims.
However, she said that on May 5 she tried to use a voucher only to be told by the reception staff at the hotel she was checking into that the voucher was not valid.
Ms Ngamta said she then checked the Facebook page of the hotel and found it had issued a warning about Ms Chatchamon and the fake vouchers she was selling.
The music teacher contacted other victims and they decided to file a group complaint against Ms Chatchamon with the CSD.
Investigators said they would look into the matter.