Washington moved quickly today to deflect accusations that it had killed 11 Pakistani soldiers in an air strike, releasing video footage which it says clearly shows its forces targeting Taleban insurgents.

The Pakistan military has accused US-led forces in Afghanistan of launching an “unprovoked and cowardly” missile attack on an army checkpoint in Pakistan’s volatile Mohmand tribal zone, further straining ties between the two allies in the 'War on Terror'.

In response, US officials said Washington regretted the “reported loss of Pakistani life”, but insisted that its forces had carried out a “legitimate strike” in the early hours of yesterday - and had given Pakistan advance warning.

Today, the US-led coalition backed those claims with video showing “precision” strikes on a group of seven rebels who sought refuge in Pakistan after attacking a coalition reconnaissance patrol in eastern Afghanistan.

The grainy black and white video footage, taken by an unmanned drone, shows a first strike targeted at men hiding behind a rock who fire two rocket-propelled grenades at coalition troops offscreen.

The US-led soldiers were attacked while trying to move to a pick up point for extraction by helicopter when they were attacked by the “anti-Afghan forces” said a commentary supplied with the video.

A huge explosion lights up the area and the militants then seek cover in a deep ravine nearby before three more bombs, one of which is not shown, land on the militants.

"It is clear there are no structures or (Pakistani) outposts in the impact area,” the voiceover says, adding that all of the militants were killed.

But an AFP photographer who reached the scene last night saw a large crater near a mud-brick Pakistani paramilitary outpost, which was badly damaged.

Local tribesmen were scraping pieces of human flesh from nearby trees, while shredded military uniforms and pools of blood littered the scene.

The incident would be the worst of its kind since Islamabad sided with the United States in 2001 against the Taliban and Al-Qaeda, and comes amid growing international unease over Pakistan’s recent negotiations with the Taleban.

“The timing is terrible,” said Bruce Riedel, a senior Brookings Institution analyst as well as a former CIA officer and advisor to three US presidents on South Asian affairs.

Pakistani security officials and residents said that the incident began when Afghan troops crossed the porous frontier and tried to occupy a strategic Pakistani post in a long-disputed area of the troubled tribal belt.

Residents said word spread in the conservative region and armed tribesmen along with Pakistani Taleban fighters arrived and attacked the Afghan soldiers, who retreated and returned later with coalition forces.

A spokesman for an umbrella group of Pakistani Taleban movements, Maulvi Omar, struck a patriotic stance by accusing Western forces of “provocative action” by bombing Pakistani territory.

“We will not tolerate it and we know how to deal with Afghan and foreign forces,” Mr Omar said.

Shah Mehmood Qureshi, the Pakistani Foreign Minister, said on the sidelines of a Afghan donors’ conference in Paris that he would raise the issue with NATO. “We have taken the coalition attack in Mohmand seriously and summoned the US ambassador and conveyed our feelings to her,” he told the private television station Geo.

In an unusually harsh statement, the Pakistani army yesterday condemned what it called a "completely unprovoked and cowardly act” and warned that it had “hit at the very basis of cooperation in the anti-terror fight".

Gonzalo Gallegos, a US State Department spokesman, said that Washington was “sad to see the reported loss of Pakistani life”, but added: “Our troops were defending themselves against a hostile act, which they have the right to do."

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