The slain woman's husband is the self-confessed chief suspect in the 31-year-old motherof-two's killing. Garda sources have told the Sunday Tribune they have obtained information relating to a threat made by "a person known to Joe O'Reilly".

Detectives learned about the planned attack on O'Reilly through information provided to them by a third party.

It remains unclear whether this person has any connection to the murder probe.

Detectives informed Joe O'Reilly about the threat to his safety but he has not asked for any garda protection to be provided.

The revelation comes just days after a vigil was held at the couple's Naul, Co Dublin, home where Rachel was found beaten to death. O'Reilly did not attend the ceremony, which was organised by members of Rachel's family to mark the second anniversary of her brutal murder on 4 October 2004. There are indications of growing tension between O'Reilly and his murdered wife's family. Rachel's parents last week placed a memorial tribute in a Dublin newspaper without making any reference to her husband.

The garda file in relation to the murder investigation is currently being considered by the office of the director of public prosecutions (DPP), James Hamilton.

Speaking to the Sunday Tribune last night, Rachel O'Reilly's father Jim Callely made a heartfelt plea for Rachel's killers to hand themselves in.

"If anyone knows anything that may help the gardai, they should come forward. They would probably feel a lot better if they did, " he said.

"We believe that there must be somebody out there who knows something about Rachel's killing. I believe that you can't do something like that totally on your own so if anybody knows anything they should come forward no matter how scared they might be."

Rachel's mother Rose and sister Ann appeared on Friday's Late Late Show to renew their appeal for information, just days before what would have been Rachel's 33rd birthday next Tuesday.

Rose said, "At the time of Rachel's death, we didn't think that nobody would be brought to justice two years later. It is a strange feeling to be in the middle of a nightmare. The sun has gone out of our lives."

In a chilling message to Rachel's killer, Rose said, "In God's name, if they want to help themselves after what they did they should go to the police and hand themselves in."