Roadside bombs have killed seven civilians and two NATO soldiers in Afghanistan.

The Afghan civilians were killed Friday when their vehicle struck a bomb in the Maywand district of southern Kandahar province. Police say four other people were wounded in the blast.

A United Nations report in July said the number of civilian deaths from roadside bombs increased by 17 percent this year compared to the same period in 2010, making them the single-largest killer of civilians in the first half of this year.

NATO said Friday that a roadside bomb killed two of its service members in eastern Afghanistan. The coalition did not release the soldiers' nationalities.

Also Friday, three Italian soldiers were killed in a road accident in Afghanistan's western Herat province. Italian defense officials say two other soldiers were wounded in the accident.

At least 439 international troops have been killed in Afghanistan so far this year.