Police in the North say that it is too early to say who was involved in the multi-million pound bank robbery from the headquarters of the Northern Bank in Belfast.
A senior detective confirmed to a press conference this afternoon that in excess of £20 million may have been stolen by the raiders.
Two senior members of staff and their families were held hostage at their homes on the outskirts of the city, and Loughinisland, Co Down, as part of an elaborate plan to raid the bank's cash centre.
It was the biggest heist of its type ever staged in Northern Ireland.
Earlier, the Minister for Justice, Michael McDowell, said it would be of huge importance if a multi-million pound robbery in Belfast were shown to have been the work of paramilitaries.
Millions of pounds believed stolen
No figure has been put on the amount taken, but estimates vary between £20 million and £30 million.
It is understood the gang went to the employees' houses on Sunday.
The officials, both keyholders, were ordered to go into work the following day as usual.
It was at the close of business on Monday that the operation to empty the vaults swung into action.
At least one lorry would have been needed to ship the cash out.
The robbery came a week after the Northern Bank, part of the National Bank of Australia group, was sold off to Denmark's biggest bank, Danske.
Detectives from the Police Service of Northern Ireland's new Crime Operations Department are heading up the hunt for the thieves.