Deputy First Minister Martin McGuinness led the condemnation of the weekend bomb attack which killed a Catholic police officer in Omagh.
The Sinn Féin leader said dissident republicans are waging a “useless war against peace.”
Speaking yesterday alongside First Minister Peter Robinson, PSNI Chief Constable Matt Baggot, and Justice Minister David Ford, Mr McGuinness said dissident violence has no role in the future of the North.
“In joining the PSNI this young man sought to protect and serve the community; to be part of defining a better future for us all.
“Whoever carried out this act offer nothing to the community and have no role to play in our future. They have betrayed the community and set themselves against the will of the people of Ireland. No cause is served by this act and let no excuse be acknowledged,” he said.
The republican leader also said the campaigns of dissident groups will fail. “While those behind this act seek to promote division and conflict let us state clearly, they will fail. The process of peace building will continue and the community is united in rejection of them,” he said.
West Tyrone MP Pat Doherty also condemned the bomb attack and described dissident republican violence as “futile.”
“I want to express my outright condemnation of this killing and extend my condolences to the family of the young victim who, only having finished college, was facing a bright future in a career he had chosen in a changed political dispensation.
“His life has now been cut short and a family has now been plunged into grief and despair because of the actions of a completely misguided few.
“Those who killed the young PSNI officer in Omagh have set themselves on a completely futile path. Rather than undermine the political and peace process and this killing will serve only to strengthen our resolve to cement the process further,” he said.
The killing of the PSNI officer was also condemned by Derry Trades Council. “For this group to sat that this action will in any way bring self determination for Irish people of bring forward any plans for a united Ireland completely ignores the developments of the last 15 years where the majority of people have voted democratically to find a new way forward and move on from the methods of the past.
“We totally condemn this murder and the disruption that dissident republicans have brought to this city over the last week,” Liam Gallagher, secretary, Derry Trades Council, said.