Sacked former garda and slum landlord Kevin Galvin, who was sentenced to six weeks' jail by the High Court last week, has been transferred out of Mountjoy to Arbour Hill prison for his own safety.
A prison source said the decision to transfer Galvin on Friday was taken amid concerns that he would be a target because of his previous occupation.
Prior to his transfer, he had been subject to special protection measures at Mountjoy, meaning he had little contact with other prisoners.
The majority of inmates at Arbour Hill are sex offenders and there are very few violent incidents at the jail, making it a much safer place for a former garda.
The development comes as lawyers for Galvin are expected to make an application for his release either tomorrow or Tuesday.
It is thought that any application would ask the court to take into account the fact that the property, located at 73 Cabra Park, Dublin, which was at the centre of last week's hearing, is now empty and that Galvin has otherwise compensated the tenants involved.
Galvin, who is challenging an earlier decision to sack him from the force, was previously convicted of providing dangerously substandard accommodation to his tenants.
He owns a number of other properties but was jailed last week over his "flagrant breach" of undertakings given by him to the High Court concerning 73 Cabra Park, which was deemed by Dublin City Council to be a fire risk.
High Court president Justice Nicholas Kearns made the committal order after the council complained that his undertaking to vacate the property of all its residents had not been complied with.
The court heard that fire-safety officials who visited the property last Tuesday found three adults and a child living there in two flats.
They were in the building despite the court being told last Friday week that it had been vacated, the council said.