The Assets Recovery Agency in Britain has frozen more property in the Manchester area worth almost £12m.
Following a High Court application, the ARA served orders on two Manchester businessmen, Dermot Craven and Brian Pepper, who have been the focus of their investigations.
The orders were the latest phase of the agency's investigation which saw 15 properties in Manchester worth around £1.2m frozen last November and December.
In the latest move, the ARA froze a portfolio of 77 properties in the Greater Manchester area which it alleges have been funded by the proceeds of financial crime and used to launder money.
The portfolio has an equity value of around £4.7m and consists largely of tenanted flats and houses operated and owned by property companies based in Sale in Manchester.
When his property firm was raided in October 2005, Dermot Craven strongly protested his innocence.
Mr Craven insisted he did not know Thomas 'Slab' Murphy, an alleged leading figure in the IRA in south Armagh, who is believed to have been one of the the targets of the ARA investigation.
Mr Craven said at the time he and his business partner, Brian Pepper, had been unjustly vilified and denied they were involved in any illegal activity.
Thomas Murphy has also denied any connection with the properties in Manchester that are under investigation.
ARA director Jane Earl said the move was the 'latest stage in one of the largest and most complex investigations the agency has ever taken'.
She said that a total of 92 properties valued at £13m had been frozen and that the investigation was still ongoing.
Last week the British government announced plans to merge the Assets Recovery Agency with the Serious Organised Crime Agency.