Rights group Amnesty International condemned Monday's suicide bombing at a camp for civilians who have fled Sri Lanka's ethnic war and said the attack should not lead to retaliation.
The blast in the north-east of the island killed at least 20 soldiers and eight civilians, with 64 people also wounded.
"The use of such attacks by one party to an armed conflict does not excuse unlawful attacks in response," Amnesty's Sri Lanka specialist Yolanda Foster said in a statement.
Amnesty also noted that the government had restricted media access to conflict areas making it impossible to verify accounts of what was happening on the ground.
"In a war with no witnesses, it is the civilians who pay the price for both parties' disregard for international humanitarian law," it said.
The bomber detonated her explosives as she was being searched by female soldiers outside the camp near Visuamadu, a northern area the military recently captured from the rebels.
The attack had already been condemned by the United Nations and the US government, which has asked the Tiger rebels to negotiate terms of their surrender to government forces.
The Tigers' decades-long armed campaign for an independent homeland has recently suffered huge territorial losses as a result of a major army offensive.
{{/usCountry}}The Tigers' decades-long armed campaign for an independent homeland has recently suffered huge territorial losses as a result of a major army offensive.
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