Villagers in southern Afghanistan expressed outrage Wednesday over the deaths of three young boys and a man they say were killed by Western troops.

The U.S. military said it had killed four insurgents on motorcycles in Kandahar province and could not confirm any civilian deaths.

But residents of the village of Kowuk, which is 20 kilometres north of the city of Kandahar, alleged U.S. forces dropped a bomb on a local house, said the CBC's James Murray, reporting from Kandahar.

In protest of the deaths, the villagers took the bodies of three boys — who looked to be between eight and 10 years old — and a man on the back of a pickup truck to the Kandahar governor's residence north of the provincial capital.

"It's common here for bodies to be displayed after death, so no one can deny that something happened," said Murray.

The father of the dead boys, Haji Abdul Rahim, told Murray his three sons died alongside their cousin. Pulling back the blanket that covered their bodies, he told Murray they were innocent Muslim children.

Helicopter strikes

Abdul Rahim said he heard a pair of helicopters circling over his compound at 1:30 a.m. Wednesday before they fired two missiles that hit his home. His brother and another son were wounded, he said.

A U.S. military spokeswoman said a helicopter had fired on four insurgents carrying jugs on motorcycles through a field away from a populated area of the local district, Arghandab. The NATO-led International Security Assistance Force said there was another explosion nearby.

ISAF said it is investigating whether the explosion was caused by its forces. But the U.S. spokeswoman offered another account.

"The helicopter engaged the militants with guns and rockets. However, the explosions heard by locals were caused by the jugs the insurgents were carrying exploding," said Capt. Elizabeth Mathias.

The deaths of civilians at the hands of foreign troops have caused deep resentment among Afghan people. President Hamid Karzai has repeatedly called on foreign troops to halt air strikes and raids in Afghan villages.

Newly appointed NATO Secretary General Anders Fogh Rasmussen acknowledged the issue of civilian casualties was a sensitive one.

"We have seen a number of civilian casualties," Rasmussen said after arriving in Kabul Wednesday to meet with Karzai. "I strongly regret that, but I can assure you that it is our clear intention to do everything possible to reduce the number of civilian casualties to an absolute minimum."

With files from James Murray, The Associated Press