Taliban insurgents killed 15 police on the main highway in western Afghanistan, officials said on Thursday, in the latest attack to highlight an escalation in rebel strikes as NATO-led troops withdraw.
"Highway One" is a 2,200 kilometre (1,400 mile) circular road connecting the key cities of Kabul, Kandahar, Herat and Mazar-i-Sharif, but it has been a constant target for insurgent attacks, kidnappings and looting.
"A convoy of police who went to inspect a highway patrol unit were caught in a Taliban ambush on Wednesday," Farah province spokesman Abdul Rahman Zhuwandi told AFP.
"There was fighting between them in which 15 national police were killed and 10 wounded, while several Taliban were also killed."
The attack occurred shortly before dusk on Wednesday in Bakwa district of Farah province, which borders Iran.
The ambush raised the death toll in Taliban attacks on Wednesday to more than 30, including an American soldier, four policemen and three civilians who died when insurgents tried to storm a joint NATO-Afghan military base in the east.
NATO-led troops are withdrawing from Afghanistan as local security forces take over responsibility for thwarting the Taliban, who have launched a spate of recent attacks across the south, east and west.
Afghan and international leaders are trying to open peace negotiations with the militants to halt the conflict before a presidential election in April and the departure of all NATO combat troops by the end of 2014.