At least 14 Afghan police and a provincial official have been killed in three separate insurgent attacks across northern Afghanistan, government and security officials say.
Under-trained, poorly paid and ill-equipped Afghan police have borne the brunt of increasingly frequent Taliban attacks in both urban and rural parts of the country, but the north has largely escaped the bulk of fighting, Reuters reports.
Newly appointed Afghan Interior Minister General Bismillah Khan last week announced plans to step up police training as local security forces prepare to take security responsibility from United States and NATO troops within four years.
Earlier, five American soldiers have been killed in separate incidents in Afghanistan.
Three died in east Afghanistan and two were killed in separate roadside bombings in the south. A sixth died in an accidental explosion.
The BBC reports more than 350 NATO soldiers have been killed this year.
Elsewhere in Afghanistan, gunmen killed 11 Pakistani Shia tribesmen in the east and a person was killed by a motorbike bomb in Kandahar.
And hundreds of Afghans have taken to the streets of the northern city of Mazar-i-Sharif in protest at increasing numbers of civilian deaths.