UPDATE 1-U.S. troops died in Taliban attempt to storm base

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By Jon Hemming

KABUL, July 14 (Reuters) - A Taliban attack that killed nine U.S. soldiers, the biggest single American loss in Afghanistan since 2005, was a well-planned, complex assault which briefly breached the defences of an outpost near the Pakistan border.

The Taliban have largely shied away from large-scale attacks on foreign forces since suffering severe casualties in assaults on NATO bases in the south in 2006. Instead the militants have scaled up hit-and-run attacks and suicide and roadside bombs.

"The insurgents went into an adjacent village, drove the villagers out, used their homes and a mosque as a base from which to launch the attack and fire on the outpost," said NATO spokesman Mark Laity on Monday.

"Some of the insurgents also then attacked. I think it looks as if they made a brief breach into the base and were repelled," he said.

Troops from NATO's International Security Assistance Force (ISAF) and the Afghan army only moved into the combat outpost in the mountainous and forested Pech Valley district of Kunar province days before and the defences were not fully constructed.

The Taliban began their attack just before dawn on Sunday.

After driving back the assault, the defenders, numbering between 100 to 150, called in airstrikes from attack helicopters and warplanes. Fierce fighting went on till mid-afternoon.