Dissident republicans granted weekend leave from prison have boasted about taking part in illegal Easter Rising demonstrations in Lurgan and Coalisland, it has been claimed.
Adrian Cochrane-Watson, an Assembly candidate for the UUP, said six convicted terrorists made the claims on return to prison.
"I have met with Prison Service staff who left me in no doubt about their revulsion that these six individuals were allowed out of Roe House and Foyle House," he said.
"On their return to Maghaberry these terrorist thugs boasted about their participation in the illegal demonstrations in Lurgan and Coalisland."
On Easter Sunday in Coalisland around 60 men and woman paraded in military-style uniform for an Easter Rising commemoration.
The march was organised by the National Republican Commemoration Committee, which has ties to prisoners held on the Roe Four landing at Maghaberry Prison, who are aligned to a group calling itself the IRA. In Lurgan masked men paraded for a march organised by Republican Sinn Fein.
After the display a masked man read out a threat from the Continuity IRA against members of the security forces.
First Minister Arlene Foster was critical of police following the displays, saying they should have acted to stop the parades.
She said: "I want to see these people behind bars. No place for masked men in Northern Ireland."
The PSNI said it gathered photographic evidence at the parades and was investigating "suspected breaches of Parades Commission determinations".
Mr Cochrane-Watson said the thought that terrorists would be granted concessions after the murder of prison officer Adrian Ismay in March was hard to take. "These are the same convicted terrorists who laughed and joked in the face of prison officers at the recent murder of their colleague in east Belfast," he said.
"They are not conforming to the prison regime and therefore benefits such as weekend home leave, particularly to celebrate dissident republican events, should have been removed. It is simply an insult to the entire community."
Mr Cochrane-Watson said he would be seeking answers from the prison authorities and Justice Minister David Ford.
The Department of Justice has not confirmed if the six inmates in question were granted home leave over Easter weekend.
A spokesman said: "Prisoners coming to the end of their sentences can apply for periods of pre-release home leave.
"With the exception of the pre-planned Christmas scheme, these periods of home leave can take place at any time throughout the year."