A 42-year-old man has been arrested after the find in the Friary Road area
The police have arrested a 42-year-old man in connection with the discovery of a viable bomb in Armagh.
The "horizontal mortar device", which the police said was capable of causing serious injury and death, was found on the Friary Road on Thursday.
The PSNI district commander said it was designed to kill police officers.
The man was detained in the Armagh area by detectives from the PSNI's serious crime branch. He has been taken to Antrim police station for questioning.
An alert began in the city after police received a report late on Wednesday night that a suspicious device had been left in the Friary Road area.
Nearby homes were evacuated and the road was closed while the operation took place.
District Commander Chief Superintendent Alasdair Robinson said the initial call by a member of the public helped them pinpoint exactly where the device had been left.
"I have no doubt the aim was to kill police officers engaged in providing a community service to the area," he said.
In September three members of a Continuity IRA gang were each jailed for 15 years for a plot to kill police officers with a horizontal mortar in Lurgan, County Armagh.
The live mortar, complete with launching tube, was found near the Cornakinnegar Road on 5 April 2007.