The joint operation between the Cyber Crime Investigation Bureau and the US Secret Service officer of the US Embassy led to the arrests of Monsaji La-ongnual, 49, and Panudet Wongnamnong, 58.
Both were arrested in Muang Thong Thani in Nonthaburi’s Pak Kret district.
The two agencies planned the operation after they received a tip-off that a ring has been selling fake US dollar banknotes to customers via social media.
Thai police and US officials planned the arrest and had an undercover policeman contact Monsaji to buy 2,000 fake notes from her.
The suspect was arrested at her condominium building when she came out of her room to deliver the fake notes to the undercover policeman.
Monsaji later implicated Panudet, saying she got the fake notes from him. The officials then had Monsaji call Panudej to deliver 7,000 more fake notes to her at a shopping mall in Muang Thong Thani and arrested him there.
Pol General Torsak Sukwimol, deputy police commissioner-general, said the printing of the fake notes was high quality and looked very similar to real greenbacks.
The two suspects were charged with collaboration to make fake foreign currency banknotes with the intention to sell.
Torsak said Thai police have detected that fake US banknotes have been spreading in Thailand and sometimes to neighbouring countries. Sometimes, the fake notes were found exchanged at money changers at the Singapore airport.
Torsak said the US dollar fake notes were often found in Laos.
Had the 9,000 notes been exchanged at exchange shops, it could have caused damage worth 34 million baht, Torsak said.