KANDAHAR, Afghanistan - Canadian soldiers struggling to contain the Taliban insurgency in southern Afghanistan killed four civilians last year, according to military figures obtained by The Canadian Press.

The deaths occurred when the soldiers felt compelled to open fire in what is known as an escalation of force.

"There were three incidents of escalation of force that led to four civilian deaths caused by CF soldiers," the military said.

"That being said, in all three cases, the investigations determined that the rules of engagement were followed."

The Canadian Forces National Investigation Service, an arm of the military police, provided no further details on the incidents.

Under the rules of engagement, Canadian soldiers first attempt to defuse potentially threatening situations by non-lethal means.

That means, for example, ordering a vehicle to stop or firing warning shots before shooting to kill.

"Canada makes every reasonable effort to ensure the safety of Afghan civilians," the military said.

"Unfortunately, the Taliban's tactics of hiding among local populations makes it difficult to entirely eliminate the risk to civilians."

Despite repeated requests, the military provided no figures on the number of civilians who were seriously injured as a result of Canadian action.

However, one source said there were several injuries. Some were the result of traffic mishaps involving Canadian armoured vehicles.

In at least one case, a 14-year-old girl in Kandahar was seriously injured when a Canadian soldier fired a warning shot.

Probes of use of force involving death or serious injury to non-combatants fall to the Canadian Forces National Investigation Service.

In 2009, 32 Canadian soldiers and one civilian -- Michelle Lang, a reporter from the Calgary Herald -- were killed, most by insurgent-laid improvised explosive devices. Scores more were wounded.

The four deaths at Canadian hands were among a record 2,412 civilian casualties in 2009, a 14 per cent increase over 2008, according to United Nations figures.

That made last year the deadliest yet for civilians since the fall of the Taliban regime in 2001.

Most of the deaths, 67 per cent, were blamed on the insurgency. International forces accounted for 596 or 25 per cent deaths.

Civilian deaths have become an increasingly touchy subject in Afghanistan, prompting recent demonstrations as well as fierce criticism from President Hamid Karzai.

They have also become a major source of insurgent propaganda.

Most of the deaths caused by international forces have been result of American airstrikes.

Canada does not carry out aerial bombardments.