A man injured when an explosive device detonated under a vehicle in Belfast is a prison officer, sources said.
The incident happened in the Woodstock Road area in the east of the city.
The extent of the man's injuries is not known.
Security sources have indicated he is a serving prison officer.
It is understood he was driving a van when the device detonated. Detectives are examining whether the bomb dislodged from the vehicle as it was going over a speed bump.
The finger of suspicion will point at dissident republicans opposed to the Northern Ireland peace process.