Heavy battles in the violence-plagued south, meanwhile, killed 75 Taliban and at least six civilians.

Adm. William Fallon, the head of U.S. Central Command, said Iran's Revolutionary Guard is supplying roadside bomb parts for the type of sophisticated and deadly bombs found in Iraq known as explosively formed penetrators.

"The Iranians are clearly supplying some amount of lethal aid," Fallon told The Associated Press during a trip to Afghanistan. "There is no doubt ... that agents from Iran are involved in aiding the insurgency."

Fallon said the U.S. would "act decisively" if the cross-border flow continues. His comments were not meant as a threat of military action against Iran but a suggestion that border interdiction efforts may need to be increased, Fallon's aides said later.

Iran has denied that it is supplying arms to fighters in Afghanistan.

Fallon said Iran is also providing development assistance in western Afghanistan, which he labeled as helpful.

NATO's International Security Assistance Force has said that three shipments of weapons originating in Iran have been intercepted in Afghanistan since April. The latest was discovered in the western province of Farah on Sept. 6.

Afghanistan has seen its heaviest fighting this year since the ouster of Taliban regime in 2001. More than 4,400 people have died in insurgency-related violence around the country, according to an AP count based on official figures.

Friday's bomb attack in western Kabul was directed against a convoy of French troops traveling in armored vehicles. It killed one soldier and an Afghan civilian and wounded many other Afghans, hospital and NATO officials said.

French President Nicolas Sarkozy condemned the attack as "cowardly and odious."

Heavy fighting in the south, meanwhile, killed about 75 Taliban militants, the U.S.-led coalition said.

On Wednesday, NATO launched a new operation in Helmand province, the world's largest poppy growing region, which has seen the heaviest fighting in Afghanistan this year.

Airstrikes were called in in the Garmsir district early Friday, killing about 40 fighters, the coalition said.

Six civilians, including women and children, died in a separate battle in Helmand province's Gereshk region on Wednesday after Taliban fighters fleeing NATO forces sought shelter in the civilians' homes, said district chief Abdul Manaf Khan.

ISAF said there were "a number" of civilian casualties caused by the fighting.

Taliban fighters attacked coalition forces from a housing compound that was later targeted in an airstrike. ISAF said it was "unaware" civilians were in the area.

In another newly reported battle, more than three dozen Taliban fighters were reported killed in a clash Wednesday in Uruzgan province, the coalition said.

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