CAMP LEATHERNECK, Afghanistan (ANTARA News/AFP) - The US defense chief held talks in Afghanistan on Wednesday, acknowledging that a series of "deeply troubling" incidents had challenged the US war effort but vowing that nothing would derail the mission to defeat Al-Qaeda and reverse a Taliban insurgency.

Leon Panetta held a series of meetings in southern Afghanistan just days after an American soldier went on a murderous rampage, shooting dead 16 Afghan civilians -- most of them women and children -- in the worst single such incident since the 2001 US-led invasion.

His spokesman described a meeting with leaders in Helmand as "excellent" but his talks were overshadowed by a bomb attack elsewhere in the southern province that killed eight civilians, a stark reminder of the cost of the conflict.

Addressing US, NATO and Afghan troops at Camp Leatherneck, Panetta conceded that the burning of Korans on a US base last month, Sunday`s killings and attacks on coalition troops by Afghan soldiers had posed difficult challenges.

"Each of these incidents is deeply troubling," he said.

"We will not allow individual incidents to undermine our resolve.

"We will be tested, we will be challenged by the enemy, by ourselves and by the hell of war itself."

But he added that "thanks to your efforts, our strategy is working".

In a sign that nerves are on edge, a group of US Marines waiting to hear Panetta speak inside a hall were asked to leave their rifles outside.

American troops typically have their rifles in hand when the US defense secretary addresses them.

A defense official told reporters there was no heightened security threat but the US troops had been ordered to leave their weapons at the door to be "consistent", as the Afghans in the hall were unarmed.

During talks with Helmand provincial leaders, Pentagon spokesman George Little said the defence chief told them that "the United States remains focused on the mission, and that recent events will not deter us from carrying it out".

Panetta`s visit coincides with a growing debate in Washington about the course of the 10-year-old war, with some skeptics in and outside the White House arguing for an accelerated draw-down of troops.

Under current plans, the United States aims to reduce its force of nearly 90,000 to about 68,000 by the end of September, with most of the remaining combat troops due to be pulled out by the end of 2014.

US officials have left the door open to a smaller follow-on force after 2014 but the spate of recent setbacks has complicated negotiations with the Afghan government for a long-term security agreement.

Later on Wednesday, Panetta was to meet President Hamid Karzai in a bid to further reassure him after Sunday`s killings in Kandahar province, bordering Helmand.

Suspected Taliban insurgents had raised tensions further on Tuesday by opening fire on an Afghan government delegation attending a memorial service for the murdered civilians, killing an Afghan soldier and wounding a policeman.

The eight civilians who died on Wednesday were killed when a minibus ran over a roadside bomb in Marja district -- the focus of a major US-led military offensive designed to clear out the Taliban in early 2010.

Sunday`s shooting spree marked the latest in a string of damaging incidents that have raised questions about the NATO war effort, including the burning of Korans that triggered unrest in which some 40 people were killed.

Panetta portrayed the shooting rampage as an isolated incident and insisted the US-led war effort was on track, with the Taliban in retreat.

Karzai described the massacre as "unforgivable" and the Afghan parliament wants the suspect tried locally -- but Panetta made clear the soldier would face US military justice, and possible execution.

US President Barack Obama also said he had assured Karzai that "the United States takes this as seriously as if it was our own citizens and our own children who were murdered".

But there are also growing concerns that Afghan soldiers being trained to take over security when US and NATO allies pull out are increasingly turning their weapons against Western troops.

Nearly one in five NATO soldiers killed this year has died at the hands of their supposed allies -- six of them Americans who were killed by Afghan colleagues after the Koran burning.

(H-RN)

Editor: Ella Syafputri
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