The man at the centre of a garda investigation into a suspected €1.76m fraud at a post office was questioned by officers throughout yesterday.
Tony O'Reilly (37), a senior manager at the Gorey branch of An Post, was arrested after he arrived by appointment at the local garda station.
Mr O'Reilly had been undergoing medical treatment since the discovery of the missing money last June.
Details of the financial irregularities were disclosed by the Irish Independent after they were discovered during an internal audit at the post office.
Local gardai called in the national fraud bureau to assist them with their inquiries and also launched a missing person investigation when Mr O'Reilly failed to arrive at work.
He was found four days later in Belfast.
His family issued a statement admitting that Mr O'Reilly had a gambling problem, which had spiralled out of control in the months previous to the discovery of the irregularities.
It is understood several million euro had been wagered in bets over that period.
A large proportion of the bets were placed via a bookmaker's online and telephone services.
In their statement, the family blamed the availability of those facilities for their son's "predicament".
The family said Mr O'Reilly was "a family man, first and foremost" and his gambling in recent months had been secretive and uncharacteristic.
They said they were seeking help for him to recover from "this illness".
They added they believed the addiction should be highlighted to prevent other families going through similar trauma.
Gardai said the man was later released without charge and a file would be prepared and forwarded to the Director of Public Prosecutions.