The police officer leading the investigation into the discovery of a 600lb bomb close to the border in south Co Down has said the device had the potential to devastate any town.

Speaking in Newry, Chief Superintendent Alasdair Robinson said a bomb of this size would kill anyone within 50m and seriously injure those within a 100m radius.

Mr Robinson said police were alerted to a suspicious van on the Fathom Road, near Newry Canal, at around 6.30pm on Thursday evening.

The road was closed off in about 12 minutes and British army technical officers were brought in to examine the vehicle.

He said the bomb was made of homemade explosives, which had been packed into two cylinders in the back of the van.

Inspector Robinson said the device was later made safe and the van has now been brought for a forensic examination. Among the lines of inquiry being looked at by police are that the bomb was an attempt to lure officers to the area, or that it was abandoned while being taken to a town.

He said that this was the third significant incident in the Newry area in the last month.

Given the road's close proximity to the border, he said it was possible the device had been brought in from the Republic.

Meanwhile, a second bomb was discovered in north Belfast overnight.

It was found under a parked car at the junction of the Ballygomartin Road and Twaddell Avenue.

Condemning the incident, Chief Inspector Ian Campbell said those who had planted the device had shown "a callous disregard for members of the public".

80 people had to leave their homes as army technical officers carried out their work, including families with young children and elderly residents.

Inspector Campbell said the "finger of suspicion" was pointed in the direction of dissident republicans.