A massive garda investigation has been launched after a viable "box bomb" was placed outside the home of a highly respected garda as his children slept inside.
The officer, who is aged in his 30s, noticed the device outside his front door on Thursday afternoon.
Senior sources said a dangerous Midlands-based Traveller gang who the garda has been investigating are the chief suspects.
The discovery of the bomb at the officer's home near Mohill, Co Leitrim, led to a major security alert and the deployment of the army bomb disposal unit.
Army experts examined the device and declared that it was a viable and sophisticated device.
A source told the Herald: "The bomb was an unusual shape as it was a box-type device rather than a pipe, but it was viable and capable of causing serious injury or death."
It is understood that the garda, who is based at a Co Longford station, is "very upset" over the incident and has said he is "extremely concerned" for his family's safety.
The officer, who the Herald has been asked not to name, has been given security advice by his colleagues.
Detectives based at Carrick-on-Shannon garda station are investigating the discovery, and there will now be an increase in armed patrols around the officer's rural home.
Senior sources said the officer has been involved in a major investigation into a notorious Traveller gang who are mainly based in Longford town and nearby Edgeworthstown.
A senior source said: "The Traveller gang have been involved in large-scale burglaries, the organisation of cannabis grow houses, huge social welfare frauds and a particularly nasty Traveller feud in the Midlands.
"An operation against them is being co-ordinated at Carrick-on-Shannon garda station, and the targeted officer has been heavily involved in many of the investigations into the crew in Co Longford.
"It seems that because of this he is hated by some of these individuals and by one criminal in particular -- this is the strongest line in the investigation now."
The Herald has learnt that the gang suspected of planting the bomb has been involved in a number of serious incidents in the ongoing Traveller feud.
These include shots being fired at cars, pipe bomb incidents, bullets being sent to rivals through the post, intimidation and destruction of property.
A member of the gang has "flooded Longford with heroin" after he paid Real IRA figures Nathan Kinsella and Alan Ryan a 'drugs tax' to allow him to deal in the town, according to sources.