An Irishman is suspected by Thai authorities of being one of the principals behind the £100 million "boiler house" share-ramping operation broken up on Thursday.
Mr Paul Hickey (48) and an Australian national, Mr Scott Fisher, were both directors of the Brinton Group, one of two unlicensed brokers raided by the Thai authorities.
The two men are to be held for up to 87 days while the authorities in Bangkok carry out their inquiries. They may appear in court today and face possible charges of violating Thai securities law. The maximum penalty for fraud in Thailand is seven years in jail. Those found to have broken trading rules can face fines in excess of £10,000.
A second Irishman, named as Mr Richard Murphy, is also believed to have been behind the two firms and is being sought by the Thai authorities.
Mr Hickey and Mr Fisher were among 84 foreign nationals arrested during the raid, most of whom are expected to be deported in the coming days after being fined in the region of £100 for working without a visa.
The Irish nationals arrested were named as Mr Hickey, Mr David Kelly (26), Mr Paul Ryan (32), Mr Paul O'Leary (31), Mr Stephen Doherty (30), Mr Neill Delahaye (26), Mr Michael Scales (26), Mr Michael Lavin (32), Mr Patrick O'Herlihy (30) and Mr Christopher Scales (23).
Mr Hickey has been living in Bangkok for the last two years and is originally from south Dublin. Those answering calls to his Dublin home yesterday declined to comment. Neighbours said Mr Hickey had not been seen at the house for a number of months.
Mr Hickey, who is also involved in a restaurant business in Bangkok, was described by those who knew him in Bangkok as a dedicated family man.
"He must have been leading a double life if this is true," said a member of the Bangkok expatriate community that has been stunned by Thursday's arrests.
Brinton Group and Benson Dupont Capital Management came to public notice in March after they were named with other firms in a report by the Australian Securities and Investment Commission (ASIC) warning investors to hang up on overseas investment promoters who telephone and put pressure on people to invest money offshore.
The two companies continued to trade despite being named as suspect by the Australian authorities.
Osiris Asia Pacific, an alias of the two companies, was also named in the ASIC report. Thursday's raids followed a two-year international investigation into the companies.
Along with similar firms in Bangkok, the companies employed young people in hothouse environments encouraging them to use hard-sell methods offering bogus "buy now or miss out" deals on stocks and futures.