A roadside blast ripped through a vehicle in southern Afghanistan Friday, killing 14 villagers and wounding three as they traveled to a provincial capital for holiday celebrations, an official said.

Funerals continued in a neighboring province for some of the dozens of civilians reported killed this week during a NATO military operation against Taliban militants that has deeply angered locals.

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Friday's blast went off near a village north of Tirin Kot, the capital of Uruzgan province. Capt. Andre Salloum, a spokesman for NATO's International Security Assistance Force, said it was caused by an anti-tank mine but it wasn't immediately clear if it was old or newly planted.

The victims, from the village of Safid Shar, had been traveling in a pickup truck or small bus to Tirin Kot to celebrate the end of the Muslim holiday of Eid al-Fitr.

In the southern city of Kandahar, mourners attended a prayer ceremony for some of the several dozen civilians who Afghan officials say were killed during NATO operations on Tuesday in a nearby district.

NATO said its initial reports found that 12 civilians were killed during three separate incidents, but Afghan officials estimated the number of civilians killed at between 30 and 80, including many women and children.

Fearful villagers on Thursday packed up vehicles and donkeys to flee the Panjwayi region, where NATO has been battling suspected Taliban militants.

Afghan President Hamid Karzai has repeatedly condemned civilian deaths caused by Western forces and only a week ago urged NATO to use "maximum caution" in its military operations after nine villagers were killed during another NATO operation in Kandahar.

Maj. Luke Knittig, a spokesman for NATO's International Security Assistance Force, said that up to 70 militants may have been killed in three separate clashes in Panjwayi. He said NATO precisely targeted militants using artillery fire and airstrikes and regretted any civilian casualties.

Villagers and local government officials denounced NATO and blamed the government for lack of security.

"Everyone is very angry at the government and the coalition. There was no Taliban," villager Abdul Aye said through tears at a mass funeral in Kandahar city on Thursday. He said 22 members of his extended family were killed.

The deaths in Panjwayi come only a month after NATO launched a major offensive there, during which more than 500 militants were killed, according to NATO.

Death tolls in remote military action in Afghanistan are difficult to accurately pin down, and estimates often vary widely.

NATO spokesman Knittig said that fighters in Panjwayi on Tuesday had attacked NATO forces, and that return fire was precisely aimed at those militants. Bismallah Afghanmal, a provincial council member, said fighters fled into civilian homes, which were then attacked by NATO forces.

Karzai said he'd formed a seven-member investigative committee.

The worst previous reported incident of civilian deaths from foreign military action in Afghanistan came in July 2002, when a U.S. airstrike in Uruzgan province killed 46 civilians and wounded 117, many of them celebrating at a wedding party.