Paris-based Action Against Hunger, or ACF, asked the French government and the European Union, among others, to set up an international panel to probe the August 2006 massacre in the Sri Lankan town of Muttur.
"ACF decided to withdraw from Sri Lanka, detach itself from the Sri Lankan legal procedures, denounce the way the procedures have been conducted in Sri Lanka and request an international investigation," an ACF statement said.
The ACF pulled out of Sri Lanka in March after accusing local authorities of dragging their feet in probing the massacre that took place at a time when government forces were locked in heavy combat with Tamil Tiger rebels.
"The ACF is launching the 'Justice for Muttur' campaign, which aims at mobilising the humanitarian community, public opinion and international decision-makers to call for the opening of an international inquiry into the Muttur case," the statement said.
In April, a Sri Lankan human rights group named members of the security forces and poli