A police officer received minor injuries after he was attacked with bricks, stones and petrol bombs while attending a security alert in Newry.
Officers were investigating a suspicious object at the Camlough Road close to the hospital last night. The device was declared an elaborate hoax.
There was disruption to those attending Daisy Hill Hospital and local businesses.
Newry and Mourne PSNI area commander, Chief Inspector David Beck, said: “You see again a small criminal element intent on bringing mayhem and disruption with absolutely nothing left to offer.”
He said a full investigation was underway.
Army bomb disposal experts were carrying out a controlled explosion when police were attacked by youths.