The RUC are set to start a major new inquiry into the Omagh bombing.
Three years after the car bombing which left 29 people dead the RUC will signal a new push to bring the killers to justice.
It will be launched in Omagh tomorrow, the anniversary of the atrocity.
A spokesman for the RUC said: "We are trying everything possible to bring the people responsible before the courts.
"We know that there are bound to be people who do have information who maybe have not come forward yet.
"It could be a very small piece of information which closes the crucial gap."
The new investigation comes after relatives of the victims started legal action seeking compensation from alleged members of the republican splinter group behind the bombing.
Bereaved families will mark the anniversary with an inter-denominational prayer service in the Garden of Remembrance near the scene of the explosion.
One man is awaiting trial in Ireland in connection with Omagh, charged with conspiracy to cause an explosion and with membership of an illegal organisation.
PA