At least 12 civilians, including five children, have been killed by a roadside bomb in eastern Afghanistan.
Another five people were injured in the attack in Paktika province, near the border with Pakistan.
The provincial governor blamed "enemies of peace who once again revealed their tyrant face to the public" - an alleged reference to the Taliban, who have not said whether they were involved.
President Hamid Karzai said the bombing was "against all principles of Islam".
Paktika has been the target of numerous attacks from insurgents in the past.
It is often used by the militants to attack US-led forces in the country.
Anger of civilian deaths
The civilians had just entered Afghanistan from neighbouring Pakistan.
They were driving through Paktika province when their vehicle hit the bomb.
Two women and five children are amongst the dead.
Roadside bombs - commonly used by insurgents - are intended for members of the security forces and officials but often kill local people instead, says the BBC's Jill McGivering.
Earlier, protesters in Kabul staged an anti-American demonstration, angry about the growing number of civilians killed by both sides.
The issue has always been sensitive - it is a source of widespread public anger and of tension between the Afghan government and the US, our correspondent says.
A few days ago, the Nato commander in Afghanistan, General David Petraeus, apologised for the deaths of nine boys, killed as they gathered firewood, after a mistake by Nato forces.
