Police sought an arrest warrant for another key suspect believed to be behind the online gambling site macau888, and searched a luxurious condominium and an entertainment place with a suspected connection to the illicit business.
Police were gathering evidence to back their request for an arrest warrant for Chaiwat Kachornboonthaworn, 37, alias Benz Daemon. He is the eldest of four brothers alleged to have operated macau888.
At 1am on Sunday deputy national police chief Pol Gen Torsak Sukwimol supervised raids at about 40 locations to look for suspects in the case. Some of the places were allegedly money-laundering fronts for the gambling website.
They included a luxurious condominium worth about 40 million baht in Watthana district. Police believed the condo belonged to the four brothers. Police found three empty safes there.
Surveillance camera footage showed that Mr Chaiwat left the condominium on Thursday night.
Police arrested eight suspects in the midnight raids.
Another location searched was an entertainment venue on Royal City Avenue in Huai Khwang district, where 113 foreign visitors were found, including 42 Chinese, 23 South Korean and 16 Singaporean nationals.
Pol Maj Gen Phanop Worathanatchakul, commander of the Patrol and Special Operations Division, said quantities of illicit drug powder and tablets were dropped on the floor of the venue.
Pol Maj Gen Wiwat Khamchamnan, deputy commissioner of the Cyber Crime Investigation Bureau, said police had sought warrants for the arrest of 13 people suspected of laundering money at numerous entertainment places that also served as meeting points.
The crackdown operation on those behind the macau888 gambling website came after TV actress Arisara "Due" Thongborisut exposed the network and those involved on her Facebook page on Jan 15. In her post, Arisara said the gambling website was run by "four brothers", all with the initial "Bor".
A source said one of the four men was her ex-boyfriend, known as "Benz Daemon". The actress and her family flew to Taiwan after exposing the gambling site.
Pol Lt Gen Worawat Watnakhonbancha, commissioner of the Cyber Crime Investigation Bureau, said the four brothers left for Hong Kong on Jan 16.