Relatives of some Omagh bomb victims have criticised a decision to spend £1m (€1.5m) of charity cash on a new trauma centre.
They say the Government should pay for the Co Tyrone medical facility.
They also accuse trustees at the Omagh Fund of making decisions without consulting them.
Michael Gallagher, whose son Aidan was killed in the Real IRA atrocity said: "It's like asking victims of a horrific plane crash to pay for hospital treatment."
Members of the support group set up by some victims' families after the August 1998 car bomb attack which killed 29 people, including a woman heavily pregnant with twins, have vowed to challenge the decision.
"This was done without any regard for the families' views," insisted Mr Gallagher.
"We are going to do everything in our power to fight the decision of the Omagh Fund."
According to a new report from trustees published today, almost £5m (€7.9m) from the Omagh Fund's discretionary trust was given to the bereaved and injured.
But £1m (€1.5m) of money raised by the charitable wing has gone to a new Northern Ireland Centre for Trauma and Transformation to be based in Omagh.
Money from this cash pot - raised from big businesses benefiting from tax concessions - cannot go to individuals.