Six men arrested after a republican commemoration heard threats of further violence by dissidents opposed to the peace process have been released without charge.
The event to mark the anniversary of the 1916 Easter Rising against British rule in Ireland was addressed by a hooded spokesman for the Real IRA who pledged more attacks on police and soldiers.
Police said they chose to maintain a distance from the event in the Creggan cemetery in Londonderry, but a security force helicopter monitored the scene.
The six men, who had been taken to Antrim for questioning, were released from custody.
The Easter Monday event was organised by the 32 County Sovereignty Movement and republicans gathered for a march and a wreath-laying ceremony.
The man clad in a balaclava and black combat gear who read a statement on behalf of the Real IRA said its campaign of violence would continue.
"The IRA will continue to attack Crown Force personnel, their installations, as well as British interests and infrastructure," he said.
The group is responsible for a series of attacks including the murder of soldiers Mark Quinsey and Patrick Azimkar outside Massereene army base in Antrim in 2009 only hours before the men were to fly out to begin a tour of duty in Afghanistan.
A spokesman for the Police Service of Northern Ireland (PSNI) said senior officers had taken the decision to run "a low-key operational response to the event".
The incident came a day after an Easter commemoration by mainstream republicans heard a call from Sinn Fein for a process of reconciliation.