He also said a number of arrests had been made in connection with 12 stamps that had already been used.
Five civil servants are expected of being involved, including a Malaysian woman. Police found their bank accounts showed transactions of at over Bt1 million a month. The information would be submitted to the Anti-money Laundering Office tomorrow, said Chatchai.
Minister of Foreign Affairs Surapong Tovichakchaikul said officials had discovered that some Thai consulates issued visas without reporting back to Thai embassies creating a loophole for visa-stamp theft gangs.
He said two people had been arrested after their passports were found to carry the stolen visa stamps.
The ministry would also ask hotel operators to record visa numbers and submits them to the ministry to help in the probe, he added.