The 2006 Trincomalee Massacre of NGO Workers, also known as the Muttur Massacre,[3] took place on 4 or 5 August 2006, when 17 employees of the French INGO Action Against Hunger (known internationally as Action Contre la Faim, or ACF) were shot at close range in the city of Muttur, Sri Lanka, close to Trincomalee.

The outgoing head of the Mission, the retired Swedish Colonel Ulf Henricsson, said that this was "one of the most serious recent crimes against humanitarian aid workers worldwide".

[9] In September 2006, under increasing pressure from the international community to investigate this incident, Sri Lanka President Mahinda Rajapakse announced the formation of a Commission of Inquiry with a mandate to look into 15 specified alleged violations, including the Muttur massacre of ACF staff.

With the dubious track record of previous Commissions of Inquiry in mind,[citation needed] a group of bilateral donors negotiated for the formation of a group of International Independent Eminent Persons (IIGEP) that, invited by the president, have the mandate to observe the investigations of the Commission of Inquiry.

UTHR names one member of the Sri Lankan Home Guard—now the Civil Defence Force—and two Police Constables based in the Muthur Police Station as perpetrators, but adds that several Sri Lanka Navy Special Forces were part of the group that entered the ACF compound and remained passive as the ACF staff were murdered.