The head of the probe, however, refused to say who had been found responsible for the 2006 massacre of the aid workers, which international monitors and rights groups have blamed on Sri Lankan government forces.
"We have completed seven cases, including the ACF (French charity Action Against Hunger) case, and we have asked for a date to hand over the report to the president," Nissanka Udalagama said.
"I can't discuss our findings because it is up to the president to decide," he added, saying his panel would ask the president to establish a more permanent body to keep up investigations.
Thirteen men and four women who worked on water sanitation and farm projects for the ACF were found shot dead in August 2006 in the northeast of the island while troops and Tamil Tiger rebels were locked in combat.
Nordic peace monitors at the time blamed the killings -- the worst attack on aid workers since the bombing of the UN headquarters in Baghdad in August 2003 -- on government forces.
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