The North's Deputy First Minister is urging people on both sides of the border to support police in the struggle against dissident republicans.
It comes a day after the PSNI said that a 500 pound bomb found near Newry may have been destined for a town centre somewhere in the North.
Martin McGuinness says the killing of PSNI officer Ronan Kerr has disgusted and united people across the island.
Police investigating the murder have been granted an extra five days to question a 33-year old man - who was arrested on Friday.
And Mr. McGuinness says condemnation of dissident groups is not enough:
Meanwhile, Police investigating the murder of PSNI officer Ronan Kerr in Omagh have been granted an extra five days to question a 33 year old man - who was arrested on Friday.
Omagh SDLP representative Joe Byrne has welcomed the call from the North's Deputy First Minister Martin McGuinness for people to help police.
And speaking today Mr. Byrne says anyone with information on Constable Kerr's death should come forward: