A DRUG trafficking gang blamed for the murder of a former garda is also believed to be responsible for the disappearance of his neighbour.
Senior investigators think the two men fell foul of the gang, whose leader is based in Co Cavan.
Retired fraud squad detective John Kerins (48), was hit by two shotgun blasts after he allowed his killer in to his home at Cornaveagh, outside Bailieborough, Co Cavan, in the early hours of Friday.
His neighbour Gerard Daly has not been seen since June last year and is feared dead.
Some months ago, gardai received information suggesting Mr Daly had been murdered and that Mr Kerins had been involved.
However, extensive checks failed to unearth any evidence to back up the theory and officers now think now the information may have been circulated for malicious reasons.
Mr Kerins was interviewed by gardai about his disappearance because the two were regarded as friends and shared an interest in dog breeding.
However, gardai think the ex-detective may have been linked to a cannabis growhouse close to his home, which was discovered in May and contained herbal cannabis with a street value of up to €100,000.
Gardai also found three cannabis plants in Mr Kerins's house when they arrested him in August in connection with charges of stealing plant and farm machinery in Cork.
Officers carried out searches in the Bailieborough area over the weekend for the murder weapon.
Gardai are hoping that the results of a forensic examination of the house, where Mr Kerins lived alone, might open a new line of inquiry.
A special case conference will be held this morning at Bailieborough garda station to review any progress.
Gardai say some of the drug trafficking suspects have connections to crime gangs in Dublin and among their associates is a dissident republican activist, who is wanted for murder.
Mr Kerins was alleged to be on the periphery of the gang but was not a major player.
Meanwhile, friends of Mr Kerins said he told them that he would "kill" whoever was responsible for the disappearance of Mr Daly.
And Mr Kerins delayed his planned marriage to second wife Shirley Quinn when his 42-year-old friend and neighbour vanished in June 2011.
The marriage was postponed but the two did eventually wed a number of months after the incident.
Ms Quinn left the home around six months ago and has told locals that she has had "nothing to do" with him since.
Anyone with informationshould contact Bailieborough station on 042 9665102 or phone the confidential line, 1800 666111.