The Department of Special Investigation has arrested an executive of QRS Education Co Ltd, Malika Maksalud, over her alleged role in a foreign exchange investment scam in which a People's Party MP Pawoot Pongvitayapanu has also been named.
Justice Minister Rutthapon Naowarat said the arrest was carried out on Wednesday morning in Bangkok's Rama IX area under a Criminal Court warrant.
Ms Malika, he said, acted as the broker for another company with a similar name, QRS Co Ltd.
She was taken to DSI headquarters for questioning and is regarded as one of the most important suspects in the investigation.
She faces multiple charges, including conspiracy to defraud the public, operating an unlicensed securities brokerage, operating an unauthorised futures trading business, importing false computer data and money laundering.
Police say Ms Malika lured investors through aggressive advertising campaigns, falsely claiming that her company was licensed by overseas regulators and guaranteeing returns of 20-30% within seven days.
Victims were invited into exclusive online groups that provided trading signals.
Authorities said the company also delayed its order execution, controlled price charts and displayed prices that differed from global market prices, causing investors to suffer significant financial losses.
When victims attempted to withdraw funds, they were allegedly required to pay additional taxes or withdrawal fees in advance or were told that technical problems prevented withdrawals.
Investigators also alleged the operation encouraged losing investors to recruit new participants as introducing brokers in exchange for salary-like returns, commissions and additional bonuses.
Her arrest came after the arrest of another suspect, Teerapong Kongkaew, widely known as "Coach James", on Tuesday at Suvarnabhumi airport.
Authorities alleged that he played a key role in promoting two forex brokers, acting as an introducing broker, training investors, and encouraging the public to invest in schemes promising unusually high returns.
Pol Lt Gen Rutthapon said 22 other suspects, including Mr Pawoot, have been issued summonses for questioning since the court declined to issue arrest warrants for these individuals.
