**At least 12 civilians have been killed in southern Afghanistan by a roadside bomb which blew up a bus, police and officials say.**The bus was travelling through Kandahar province when it hit the device, police chief Bismullah Khan said, adding that 15 other civilians were injured.
Another official blamed Taliban insurgents for planting the bomb.
Militants often use such devices to attack the military, but they kill many more civilians than they do soldiers.
Provincial government spokesman Zalmai Ayoubi told Reuters news agency that women and children were among the dead.
He blamed the Taliban and said a similar blast on the same road had killed three civilians a day earlier.
The deaths come shortly after Anders Fogh Rasmussen made his first speech as secretary-general of Nato. Speaking in Washington, the former Danish prime minister called on European nations to stand with US forces in Afghanistan.
Rising military casualties in Afghanistan have undermined public support for the operation in many European countries.