A man and a woman arrested separately in Belfast yesterday morning are still being questioned about last December's £26.5 million (€38.6 million) Northern Bank robbery in the city.
They are being interviewed by detectives at Antrim police stations
The Garda and PSNI have insisted the IRA carried out the robbery, although the IRA denies this.
This month three men were charged in connection with the heist. In all, this month 10 people were arrested by PSNI detectives investigating the crime.