An under-car booby-trap bomb has been found in the driveway of an Army major's home in Bangor, County Down.
It is understood the device fell off the vehicle on Wednesday morning and was found by the soldier.
Dissident republicans are being blamed for the attack. Between 20 and 30 houses in the Chatsworth area of the town have been evacuated.
Army bomb disposal experts are at the scene and a controlled explosion has been carried out.
The attack came a day after a car bomb exploded outside a police station in Londonderry.
No-one was injured in the explosion but several buildings were damaged in the attack which has also been blamed on dissident republicans.
On Wednesday, local DUP assembly member Peter Weir said those who had carried out the attack in Bangor were "intent on murder".
"These terrorists have no support in the community and are beneath contempt.
"At this time the thoughts of everyone go out to the soldier and his family who have been callously targeted by these lawless criminals," he said.
"I have no doubt that by their actions, the criminals are trying to send a message that they can come in to a law-abiding and peaceful part of Northern Ireland in order to peddle their own brand of evil.
"They are mistaken."
SDLP justice spokesperson Alban Maginness said the attack suggested a high level of intelligence is in the hands of those responsible.
"This is disturbing," he said.
"This attack suggests that the intelligence at the disposal of the perpetrators - and at the moment we can only speculate - is of a worrying level.
"There should be a full and frank statement from the PSNI indicating who is responsible for this attack that informs on the nature and capacity of the explosive device, on how sophisticated it was."
Palace Barracks, one of Northern Ireland's main army bases is just a few miles from Bangor.
In January, dissident republicans seriously injured a police officer in a booby-trap bomb attack in County Antrim.
That followed an attempt to kill a policeman in east Belfast when a similar device exploded under his girlfriend's car.