U.S. officials are expressing relief that Sri Lanka's civil war is over, while calling for clarity on who is responsible for "the tremendous loss of life" in recent months.
In the most direct comments since the fighting stopped, the United States is expressing support for international calls to determine if human rights laws were violated during the final phase of the fighting between Sri Lankan forces and Tamil rebels.
Outgoing spoke at a news conference Wednesday in the Sri Lankan capital.
"On the question of war crimes we think it's important for the international community to have more information about what happened on both sides during the recent offensive in northern Sri Lanka," said Blake. "And that's one of the reasons that we press for access for the ICRC and the U.N."
Ambassador Blake has been nominated by President Obama to be the State Department's Assistant Secretary for South Asia.
On his last official day as U.S. ambassador, Blake responded to reporters who questioned whether Washington had spoke out forcefully enough during the past few weeks when both the Sri Lankan government and the rebel Liberation Tigers of Tamil Eelam, claimed the other was deliberately killing civilians.
"They were trapped by the LTTE and were effectively used as human shields. But we also called on the government to abide by its own commitment not to use heavy weapons in the safe zone," he said. "I think there were some violations there."
Colombo says its troops did not kill civilians but rather accomplished the world's largest successful hostage rescue mission, freeing tens of thousands of Tamils from the LTTE.
The United Nations says it remains unclear if the combat zone has been cleared of all civilians, especially the injured and the infirm. The U.N.'s Secretary General Ban Ki-Moon will arrive late Friday to press the country's President for access to the area and the government-supervised camps, housing more than 200,000 Tamils displaced by the fighting.
The military is continuing to hunt for remnants of the Tamil rebel force which at its peak controlled one-third of the country. Eight rebels were killed in two incidents Wednesday about 180 kilometers south of where the final battle took place Monday.
In the capital on the day the President declared as a national victory holiday, small groups of young people celebrated, carrying the national flag, dancing and singing.
But no official public celebration in Colombo has been announced. The city remains on a high state of alert amid fears remaining Tamil Tiger urban cells could attempt suicide bombings, a terror technique they brought to the world's attention.
Troops with automatic weapons patrol the streets of the capital and numerous checkpoints remain in place.
The head of the Defense Ministry's national security media center, Lakshman Hulugalle, says it is premature to relax their guard.
"Until all those things are healed we have to have the security because we have to be, at least, vigilant for the next two to three years," he said.
Tamil minority neighborhoods are quiet with most people remaining indoors amid a state of anxiety about what the rebel's total military defeat means for them.
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