Canadian troops in Afghanistan helped in the aftermath of a truck bombing Thursday, one day after Canadian and NATO troops killed 28 Taliban fighters and just hours after insurgent rockets hit a nearby NATO base.

The clashes took place in southern Afghanistan, said CTV's Steve Chao, reporting from Kandahar. No Canadians were killed or wounded in the fighting.

Three rockets landed in the NATO base at Sperwan Ghar early Thursday.

Less than two hours later, a young Afghan man was killed and a 10-year-old Afghan boy was wounded when the burned out hulk of a gravel truck hit by a roadside bomb exploded for a second time.

Chao said the boy, who suffered from leg injuries, is being treated by Canadian medical staff at the military hospital at Kandahar airfield.

"Time and again Canadians have been trying to help Aghans as much as possible because often it's the civilians that are caught in the middle in this battle between the Taliban and NATO forces," Chao told CTV Newsnet.

Late Wednesday, Canadian troops called in a NATO air strike in the deadly clash that left 22 suspected insurgents dead.

Canadian troops and Afghan police located a Taliban position in Shari district, and sent in the air strike, district police chief Ghulam Rasool Aga told The Associated Press.

Canadian troops had exchanged fire with a group of insurgents who attacked them, but there were no reports of casualties, said Canadian military spokesperson Lieut.-Cmdr. Kris Phillips.

In fighting earlier Wednesday in Zhari district, Afghan police fought with Taliban fighters for three hours. The battle claimed the lives of six Taliban fighters and wounded another four, Aga said. One police officer and three villagers were wounded in the clashes.

Chao said there has been evidence recently that new fighters have travelled across the border from Pakistan to bolster the Taliban ranks, spurring renewed fighting.

Chao said NATO commanders have struggled to reign in the Taliban, and realize they must do so in order to win the hearts and minds of the Afghan people.

"It's a point of frustration for NATO forces," Chao said. "And it's the reason why NATO's top commander (Lieut.-Gen. David Richards) has stressed time and again that they have to focus on reconstruction, that they have to improve the lives of Afghans in order for them to begin supporting NATO and supporting the current government under President Hamid Karzai."

Meanwhile, a new U.S.-funded poll released Thursday found Afghans are losing confidence in the direction their country is headed, even though most feel more prosperous now than they did under the former Taliban regime.

The poll was conducted by the Asia Foundation and paid for by the U.S. Agency for International Development.

 Roughly 44 per cent of the 6,000 surveyed felt the country is headed in the right direction -- a significant drop from a 2004 survey that found 64 per cent agreed with the way things were going.  Still, almost 90 per cent of the peopel surveyed said the trusted the Afghan National Army, and 86 per cent trusted the police.

Afghans listed corruption and bad governance, rather than the lack of security, as reasons they felt their country was headed in the wrong direction.

Afghanistan is in the midst of its deadliest period since the Taliban's ouster. More than 3,100 people, about a third of them civilians, have been killed in the Taliban-led insurgency and operations by foreign forces.

With files from The Associated Press