In Afghan civilian shootings, Obama vows to ‘spare no effort’ in probe, punishment

President Barack Obama promised Tuesday that the United States will "spare no effort" in its investigation into the slaughter of 16 Afghan civilians, apparently by a U.S. soldier, and vowed that anyone tied to the massacre would be punished.

"I've directed the Pentagon to make sure that we spare no effort in conducting a full investigation. I can assure the American people, and the Afghan people, that we will follow the facts wherever they lead us and we will make sure that anybody who was involved is held fully accountable with the full force of the law," he said in the Rose Garden of the White House.

Defense Secretary Leon Panetta said earlier that the U.S. Army Sergeant suspected of the crime could face the death penalty.

Obama, speaking publicly about the tragedy for the third straight day, also worked to reassure Americans who have soured on the country's longest war that he will stick with a plan to withdraw U.S. troops by the end of 2014.

"Make no mistake, we have a strategy that will allow us to responsibly wind down this war," said the president, whose remarks had initially been billed as an announcement of a new trade case against China.

Obama's comments came as he faced mounting pressure to accelerate the withdrawal timetable, with some of the Republican presidential contenders openly saying the time has come to reconsider the decade-long U.S. presence in Afghanistan.

The president said he met Monday with General John Allen, who commands NATO's 130,000-strong International Security Assistance Force (ISAF) in Afghanistan, and with the U.S. Ambassador, Ryan Crocker, ahead of talks beginning Tuesday with visiting Prime Minister David Cameron of Britain, whose country is the second-largest troop contributor to the ISAF.

Obama noted that his current strategy called for withdrawing another 23,000 soldiers from Afghanistan by summer's end, in addition to about 10,000 pulled out last year.

"We will continue the work of devastating al-Qaeda's leadership and denying them a safe haven. There's no question that we face a difficult challenge in Afghanistan. But I'm confident we can continue the work of meeting our objectives protecting our country and responsibly bringing this war to a close," Obama said.

The president, who said Monday that the shooting was the work of a "lone gunman who acted on his own," stressed that "the killing of innocent civilians is outrageous, and it's unacceptable. It's not who we are as a country and it does not represent our military."

"The United States takes this as seriously as if it was our own citizens and our own children who were murdered," Obama added.

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