A suicide attacker rammed a car bomb into an Afghan-NATO military convoy in northern Afghanistan on Thursday, killing at least six police.
The officers were on a patrol in the Imamsaheb district of north-eastern Kunduz province when they came under attack from insurgents, according to district administrator Mohammad Ayoub.
"Six policemen were killed and several others, including two US soldiers, were injured," he says.
NATO's International Security Assistance Force could not immediately confirm the attack, AFP reports.
Mr Ayoub said the bomber was driving a car filled with explosives, which detonated on hitting the convoy.
New guidelines for troops
The commander of US and NATO forces in Afghanistan, General David Petraeus, has issued new guidelines to troops.
He is emphasising the need to reduce civilian casualties, but stressing the right of NATO forces to defend themselves.
The BBC reports the emphasis on the prevention of civilian deaths was a legacy of his predecessor, General Stanley McChrystal, who was sacked in June.
Some in the military had criticised the rules, saying the emphasis on civilians put the lives of troops at risk.
As such, there was some speculation that General Petraeus would scale back the restrictions, but he is not doing so.
