In the biggest battle of the Afghan winter, NATO forces say they killed or severely wounded 130 insurgents who crossed over from Pakistan in a bold raid that underscored the dangers the lawless frontier poses for Western troops battling the Taliban.

Across the border, the Pakistan military, acting on intelligence provided by the U.S.-led coalition, attacked supply trucks used by suspected insurgents for cross-border attacks, spokesman Maj. Gen. Shaukat Sultan said.

It was the Pakistan's army first reported attack in the North Waziristan tribal region since a controversial September peace deal between the government and pro-Taliban militants that critics say has provided a sanctuary for insurgents. Sultan said it wasn't clear if any militants were killed in the Pakistani assault.

NATO tracked the militants through air surveillance while the fighters were still in Pakistan. Once they crossed over, NATO and Afghan soldiers attacked the two separate groups with groundfire and airstrikes during a nine-hour engagement that began Wednesday evening.

Gen. Murad Ali, the Afghan army regional deputy corps commander, said the insurgents had traveled into Paktika province with several trucks of ammunition. Lt. Col. Paul Fitzpatrick, a U.S. military spokesman, said it was likely the fighters were going to launch an immediate attack given the size of their group.

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Fitzpatrick said late Thursday that 130 fighters were killed or wounded. NATO initially said in a statement that as many as 150 fighters had been killed. The Afghan Ministry of Defense estimated the toll at 80 dead.

It was not clear why there was such a disparity in the estimates. As is common with violence in Afghanistan, independent confirmation of the death toll at the remote battle site was not immediately possible.

Fitzpatrick said commanders lowered the estimate during the day after further evaluating reports from observers made at nighttime in difficult conditions.

"Obviously people aren't going through a turnstile and doing a head count," he said.

NATO spokesman Maj. Dominic Whyte said air and ground assets with imaging capabilities were used to estimate the number killed. He said the estimate was "pretty accurate" but not likely the exact figure.

In early December NATO said it had killed 70-80 fighters in Helmand province but days later said that only seven to eight were killed.

Dr. Muhammad Hanif, who claims to speak for the Taliban, said in a text message to an Associated Press reporter in Pakistan that the figure of 150 dead was "a complete lie."

"The Americans want to boost morale of their troops while making such claims," the message read.

Taliban militants last year launched a record number of attacks, and an estimated 4,000 people died in insurgency-related violence, the bloodiest year since the U.S.-led coalition ousted the Taliban regime in late 2001.

In Helmand province, meanwhile, NATO airstrikes on a suspected Taliban compound Thursday killed 16 suspected militants and 13 people kidnapped or captured and being held by the Taliban, said Helmand provincial police chief Ghulam Nabi Malakhail. A civilian home was damaged and an unknown number of civilians wounded in the strike, he said.

The fight in the Bermel district of Paktika province is the first major engagement of 2007 and appeared to be the largest battle since a multi-day operation killed more than 500 Taliban fighters in the Panjwayi district of Kandahar province in September.

Whyte said NATO forces identified the group of fighters while they were still in Pakistan. Fitzpatrick said between 150 and 200 fighters moving in two groups crossed over the border.

The large group of fighters moving in an area where the Pakistan military has several checkpoints would raise questions about the Pakistan military's effectiveness in stopping militant activity.

But the U.S. assistant secretary of state for South and Central Asia, Richard Boucher, on Thursday praised Pakistan's commitment to fighting terrorism and said the country remains an important U.S. ally.

"Pakistan does not want to see Al Qaeda, Taliban operating in Pakistan and they are taking a series of steps ... to try to control those (border) areas better and we are supporting that," Boucher told reporters in Kabul.

Pakistani army spokesman Sultan said Pakistan's attack on Wednesday night, using artillery and mortars, demonstrated how it could act swiftly and effectively if it was given "real-time" intelligence on cross-border militancy.

"We don't deny that some people are coming from this side. That's why we seek intelligence in real time. We are keen to stop it," he said.

The September peace deal in North Waziristan, which lies opposite Afghanistan's Paktika province, ended bitter fighting between pro-Taliban militants and the Pakistani army. But U.S. and NATO military officials have voiced concern that cross-border attacks into Afghanistan the deal was meant to stop have only escalated, and pro-Taliban elements have gained more power.

In the southern province of Kandahar, meanwhile, thousands of mainly ethnic-Pashtun tribesmen pelted stones at a Pakistan border post and chanted "Death to Pakistan's links to the Taliban" during a rally to condemn new border measures.

The protest was held in the Afghan border town of Waish, across from the Pakistani town of Chaman near where Pakistan opened its first biometrics system to screen travelers as a measure against the cross-border movement of militants.

Pakistan has also announced plans to build a fence and plant land mines at selected places along the border, a proposed measure opposed by Afghanistan.

Afghan officials have repeatedly said that leaders from their country's insurgent Taliban militia are hiding in Pakistan and stage attacks against Afghanistan's U.S.-backed government from there. Pakistan denies the Afghan charge.

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