A suspicious object originally deemed to have been an elaborate hoax bomb was actually a viable explosive device, police have said.
The object was found on the Springfield Road in west Belfast on Thursday.
After a lengthy security alert, police declared the item as a hoax.
However, on Friday police changed position, explaining that further detailed examination had determined the device was viable.
Further searches were conducted by officers in the Springfield Road area on Friday morning and additional evidence relating to the investigation was recovered and removed for forensic examination.
PSNI Detective Inspector Paul Rowland said: "I would like to reassure the public that the items recovered today did not, at any stage, pose a risk to the public.
"There are people who will know information about those responsible for this device and I would appeal for them to come forward and speak to police."