A couple and their three children, the youngest aged 18, escaped injury when a pipe bomb exploded outside their home on Wednesday night.
Army Technical officers and police attended the scene at around 9.20pm in Patrician Park, Newry.
Damage was caused to the front of the house and a car parked outside.
A police spokesman said no motive had yet been established and made an appeal for witnesses.
The Alliance party justice spokesman Stewart Dickson condemned those behind the attack.
“Somebody could have been killed in this attack,” he said. “The people responsible have no regards for the consequences of their actions.
“There is no place for violence on our streets. We should be thankful that nobody was hurt in this attack.
“If anybody has any information about this pipe bomb attack then I would urge them to contact the Police.”