Police in North today continued to question one of six people arrested during investigations into a raid on the Castlereagh Intelligence centre last week.
The four men and two women were arrested as part of the police and army investigation in Belfast and Derry.
Those released are believed to include two leading republicans and one civilian employee at the Castlereagh base.
There were reports today that the security forces were making further searches on the outskirts of west Belfast as the hunt for items taken in the Castlereagh break-in continued.
Republicans said the police and Army swooped on houses in the Poleglass area.
Sinn Féin’s Mr Alex Maskey said the latest security operations were provocative and challenged the nationalist SDLP, which is part of the new policing arrangements in Northern Ireland, to state its position on the swoops.
The arrest of six nationalists for questioning in connection with the break-in arrests sent shockwaves through the peace process with unionists warning that there could be grave consequences.
But Sinn Féin denounced the detentions as "ridiculous" and "highly provocative" since they occurred as republicans prepared to commemorate the 1916 Easter Rising.
Mr Maskey dismissed suggestions that republicans were involved in the raid at Castlereagh, claiming it was "insulting to people's intelligence".
After the St Patrick's night break-in, Northern Ireland Secretary Dr John Reid appointed Sir John Chilcot, a former Permanent Under Secretary at the Northern Ireland Office, to head the British government investigation of events at Castlereagh police station.