A large car bomb exploded outside the court house in Newry city centre tonight.
It is understood the gates at the court house were badly damaged in the blast. The car had been reversed into the gates before it was abandoned.
The PSNI said they received warnings around 30 minutes before the explosion went off, and were in the process of clearing the area when the bomb exploded. There were no reports of any injuries.
There were reports the bomb was heard by people living up to four miles from the scene.
It comes only days after an unexploded mortar rocket was abandoned outside a PSNI police base in the nearby County Armagh village of Keady.
The area around the heavily fortified courthouse remains sealed off as British Army troops check for further devices.
It is understood to be the largest bomb explosion to be heard in the North of Ireland in several years. It follows a series of devices by breakaway IRA groups which have been abandoned, have failed to explode or only partially detonated.
Last month, a member of the PSNI was serious injured when a smaller device exploded underneath his car.
Local Sinn Fein MP Conor Murphy said: “The fact that we’re in the process of devolving policing and justice powers and there’s an attack on a courthouse will not be lost on people.
“These people are trying to drag us backwards and ensure we have the British army back on the streets.”
The bomb was also condemned by unionists and the SDLP.