One of the key figures in the Flood tribunal was arrested after arriving at Dublin Airport yesterday with £200,000 in cash in a bag and an additional substantial sum in cheques.
The man had flown in from the Isle of Man where he had earlier collected the money, consisting of about £90,000 in Irish pounds, over £100,000 in sterling and another large sum in the form of cheques.
He was being questioned by Criminal Assets Bureau detectives last night in a Dublin Garda station.
The man, expected to be one of the main witnesses at the tribunal, had earlier contacted a bank in the Isle of Man to arrange to collect the cash. He flew to Man yesterday morning and detectives were waiting for him at Dublin Airport when he returned.
He was taken to Harcourt Terrace Garda station where he was being questioned about suspected tax offences. CAB detectives were also searching the man's house in west Dublin last night.
The arrest was made by CAB detectives, led by bureau head Chief Supt Fachtna Murphy. The man was being held under Section 4 of the Criminal Justice Act. This means he can be held for up to six hours, and a further six hours on the authorisation of a Garda superindendent.
At the Flood tribunal the man has been the subject of a number of serious allegations involving corruption in planning. These have been made by retired building company executive Mr James Gogarty in his evidence to the tribunal over the past month. Mr Gogarty has alleged that the man made improper financial gains through his links to developers in Dublin.
The man, who has filed a limited affidavit denying Mr Gogarty's allegations, has also been the subject of intense speculation in recent weeks as to whether he intends co-operating with the tribunal. He had held a number of informal and, it is believed, formal talks with tribunal lawyers.
However, the outcome of these has been inconclusive. Gardai in Harcourt Terrace have also been leading the investigation into leaks from the tribunal. In recent weeks they have contacted all the parties to the tribunal in connection with their investigations.
The chairman of the tribunal, Mr Justice Flood, called in the Garda last December following a series of leaks of confidential tribunal documents to various newspapers.
Earlier this month Mr Justice Flood said the Garda investigation was "at an advanced stage". The Garda has been in touch with the Director of Public Prosecutions in relation to the matter, he said.
The man held a number of very senior positions in local administration in the 1980s, but has been retired for over a decade.
A regular attender at the tribunal since Mr Gogarty began giving evidence last month, the man who was being questioned last night is known to be concerned at the cost of legal representation at the tribunal, and the risk that the State will not cover these costs.
He was not present at yesterday's hearing in Dublin Castle, which was adjourned early after Mr Justice Flood said Mr Gogarty was feeling unwell.