Police arrested 93 suspects, mainly Indian nationals, during the raid at Asia Pattaya Hotel in Chonburi's Bang Lamung district in the early hours of Monday.
They also seized gambling tables and chips, playing cards, CCTV cameras and smartphones after finding the suspects playing cards and other games in the hotel’s Sampao room.
Taken into custody were 83 Indians, four Myanmar nationals and six Thais.
Police said Sitranan Kaewlor, 32, confessed that she had charged the Indian tourists 50,000 baht each to cover their accommodation, food, flights and transportation. She had rented the hotel room for 120,000 baht as a gambling den for the Indian visitors, police said.
They added that Thai suspects confessed that a bribe of 2 million baht was paid to government officials to ensure the illegal casino would be permitted to operate undisturbed.
The bribe claim is being investigated and any officials found guilty will face punishment under the law, Pattaya police chief Col Thanapong Phothi said on Tuesday.
He said the suspects have been separated into two groups: the gambling den operators and the Indian gamblers.
The gamblers are being kept in custody to allow for further investigation as the investigation is considered important, he said.
Police are preparing to submit the case against the suspects to Pattaya Provincial Court.