An explosive found in a busy shopping district in Northern Ireland may have fallen from a vehicle, police have said.
The device was discovered in Market Place, Lisburn, on Saturday afternoon, forcing businesses to be evacuated and streets closed as a controlled explosion was carried out.
A vehicle was later seized by detectives in the Lagmore area of Belfast.
The explosive was described by police as viable and was taken away for forensic examination.
Superintendent Brian Kee said: "Our investigation into the circumstances surrounding this security alert is at a very early stage. We are following a number of lines of inquiry, one of these is that the device may have fallen from a vehicle."
The Market Place area of Lisburn was shut down for several hours while bomb squad officers examined the scene.
Mr Kee added: "The device was discovered in the centre of the city on a busy Saturday afternoon where, had it exploded, it could have killed or injured anyone in the vicinity.
"This completely reckless act not only endangered members of the public but also caused mass inconvenience and disruption.
"Those responsible for this device have shown total disregard for the safety of the community."
Police have appealed for anyone with information or anyone who saw anything suspicious in the Market Place area of Lisburn to come forward.
Jennifer McCann, Sinn Fein MLA at Stormont for West Belfast, condemned the incident.
"The discovery of a bomb in Lisburn and a follow up search operation in the Lagmore area of west Belfast is very concerning and must be condemned," she said.
"Thankfully no one was injured in this incident.
"There can be no place for, and no justification for attacks like this in our society.
"This community is moving forward and does not want to be dragged back to the past with things like this."