Canada's foreign minister has pledged continued military support to Afghanistan.

Peter MacKay told Afghan President Hamid Karzai in Kabul Sunday, some 2,500 Canadian soldiers will continue to serve in his country.

The Canadian troops are mostly based in the volatile Kandahar province. Since 2002, 44 Canadian soldiers have been killed in the war-torn country.

Also Sunday, a roadside bomb in eastern Khost province killed two women and two children, and wounded two men traveling in a private vehicle.

In southern Helmand province, unidentified gunmen shot dead a school principal.

Authorities blame militants fighting the government for the attack on the family.

The southern provinces saw renewed fighting last year, as Taleban-led insurgents stepped up attacks against coalition and Afghan forces. Some 4,000 people died in the violence across the country in 2006.

Some information for this report was provided by AFP.