Dissident republican paramilitaries placed an explosive device near the town of Newcastle in Co Down in an attempt to kill police a police chief has said.
Police said explosives set to be used to murder officers in an attack near were discovered following a major security operation.
Chief Superintendent Robert Robinson, the district commander for the area, described the find as significant. He said: "This appears to have been an attempt to kill police officers going about their duty of serving the whole community.
"It's my belief that dissident republicans were responsible for this attempt on the lives of my officers." The success came as Chief Constable Hugh Orde warned the threat from renegaderepublican organisations the Real IRA, which murdered 29 people in the Omaghbomb atrocity, and the Continuity IRA remains high.
With both outfits determined to wreck the embattled Northern Ireland peace process, detectives on both sides of the border have been on full alert for fresh attacks.
Officers and army bomb experts were called to the Hilltown Road just outside Newcastle last night after reports were received of people acting suspiciously in the area.
The explosive device was found at the roadside, fuelling suspicions that members of the security forces were the bombers' target.
Even though police sources disclosed the find was not "a massive landmine" officers were certain it could have killed and seriously injured anyone caught up in the blast.
Controlled explosions were carried out on the bomb and a number of items were taken away for forensic examination.
As he appealed for any witnesses to help detectives find the gang who planted the device, Mr Robinson added: "These people have nothing to offer anyone. "Many members of the public use this road and the dangers to which they have been exposed are self-evident."