Sinn Féin has called on loyalist paramilitaries in Northern Ireland to say whether republicans are under threat.
Party chief negotiator Martin McGuinness demanded urgent clarification after police delivered warnings to nationalists in Derry City, south Derry and north Antrim.
They were told their details were in the hands of the Ulster Volunteer Force during overnight visits.
"It is completely unacceptable that people's personal details have turned up in UVF hands and that numerous people are now frightened and disturbed by these revelations," Mr McGuinness said.
"Given the fact that the UVF is the unionist paramilitary gang linked to these threats then it is now over to that organisation and the Progressive Unionist Party [which gives political advice to the UVF] to make urgent statements explaining this turn of events and making it clear what threats exist or don't exist."
Sinn Féin North Antrim Assemblyman Daithi McKay has linked the visits to the court appearance of a man on Friday, who was charged with various terror offences including UVF membership.
Darren Leslie Richardson (30) of Moneynick Road, Randalstown, Co Antrim, was charged with being a Loyalist terrorist and accused of being a member of the outlawed Ulster Volunteer Force.
The factory manager was further charged with the possession of documents likely to be of use to terrorists and possession of a quantity of 9mm ammunition at his place of work, the Wrightbus plant at Galgorm outside Ballymena, Co Antrim between a date unknown and April 11th.
PUP leader Dawn Purvis said she had no knowledge of any plot.
"My understanding from the PSNI is that there's no threat to anyone but that the PSNI have a responsibility to inform someone under the human rights legislation if their details or names are found in the hands of someone," she said.