At least six children and three adult civilians have been killed in a suicide attack on a Nato convoy in the Afghan province of Uruzgan, police say.
Nato is involved in almost daily clashes in the south of Afghanistan
Uruzgan police chief Qasim Khan told the BBC that the attacker drove his vehicle into the convoy in the provincial capital, Tarin Kowt.
A Nato spokesman said that one of its soldiers was killed in the incident.
The BBC's Bilal Sarwary says that never before have so many children been killed in an Afghan suicide attack.
Our correspondent says that the scene in Tarin Kowt was one of chaos and carnage, as the attack - which destroyed a Nato vehicle - took place near a crowded area during the Afghan week-end.
Women and children were among thje 11 people injured.
Another suicide attack also took place on a Nato convoy in the southern city of Kandahar, police say.
Kandahar police chief Esmatullah Alizai told the BBC that five civilians were injured in the attack.
There has been no comment from Nato as to whether any of its personnel was injured in the two attacks.
But the alliance has said that one Nato soldier was killed and three injured in a separate attack on Friday in Kandahar province.
Elsewhere, US-led forces in the south say they have killed at least 24 Taleban fighters in a number of clashes.
They say that a civilian also died in one of four separate battles in the provinces of Helmand, Zabul and Kandahar.
There has been no independent verification of the reports.
A US-led coalition service member was also killed during a clash in the east of the country on Friday, the coalition said in a statement.
Correspondents say that the south of Afghanistan has been the centre of the Taleban's insurgency, with daily attacks on Afghan and foreign forces.
Civilians are often caught up in the fighting.
Meanwhile, Nato defence ministers meeting in Brussels have been discussing the high number of civilian casualties in the war in Afghanistan.
The BBC's defence correspondent says that although the ministers are concerned about civilian deaths, they are not expected to make any major changes to military tactics.
Around 2,000 Afghans - civilian, military and insurgent - are estimated to have been killed in Afghanistan so far this year.
The defence ministers said they would try to improve co-ordination between Nato, US-led and Afghan forces, but they laid the blame for civilian casualties on the Taleban, who they say deliberately draw fire into civilian areas.