The Irish boss of a massive "boiler room" share trading operation is to appear in a Thai court today, having come out of hiding at the weekend and surrendered to police in Bangkok.

Nenagh Tipperary-born Mr John Martin Kealey presented himself to officers of Thailand's Economic Crime Division together with another Irishman, Mr Ronan Joseph Murray.

Both are directors of the Brinton Group, which was raided by Thai police last month.

Mr Kealey, who gave an interview while in hiding in a friend's apartment - in which he denied involvement in illegal activities - is believed to be the head of the operation.

Last week, he said: "We were told by legal counsel that we did not need to have a licence because we were not selling to Thais."

Both Mr Kealey and Mr Murray were immediately arrested when they came out of hiding and charged with acting as stockbrokers without a permit, violating the Securities and Exchange Act, and with fraud.

Police Major Ekkarat Mepreecha, of the Economic Crime Investigation Division in Bangkok, confirmed the two were Irishmen in their 30s. "We will detain them for interrogation. Bail is out of the question for now," he said.

Mr Kealey's passport had already been confiscated. A third Irishman, Mr Paul Hickey, is already in custody, accused of running unlicensed securities services. Australian Mr Scott Fischer, two British men, Mr Steven Hooper and Mr Adrian Roberts, and American Mr Jason Rich are also being held.

Nearly 100 people, including 34 British and eight Irishmen, were arrested when Thai police, working with the Australian Federal police and the FBI, raided Brinton Group and Benson Dupont Capital Management, two "boiler room" operations which were accused of "cold selling" shares internationally by telephone.

The Australian Securities and Exchange Commission estimates that victims had lost hundreds of millions of US dollars to these two companies and similar operations based in Bangkok.

A week ago, Mr Kealey claimed in a newspaper interview that he was trading in legal shares and was not responsible if some of his traders did not have the proper papers.

Mr Hickey, who is from south Dublin, has rejected the claim that investors were duped, saying they were dealing in "real shares and real companies".

Speaking last week from the cell where he and his colleagues were being held pending the conclusion of police investigations, Mr Hickey said the Brinton Group was a victim of guilt by association.

Mr Kealey and Mr Murray are expected to appear in court today.