At least nine policemen have been killed by a bomb in the western Afghan province of Farah, officials say.
They say the roadside bomb exploded as the police were travelling to the district of Bakwa.
The dead included a local district police chief who had only recently been appointed to his post.
It is not clear who carried out Monday's attack. Correspondents say Taleban fighters have been stepping up activities in the province recently.
The remote-controlled bomb blew up just before noon local time, Afghan officials said.
"The newly-appointed security head of Bakwa was... among the dead," Khair Mohammad Baryali, a senior security official in Farah told Reuters news agency.
One of the police vehicles was destroyed by the blast.
The Taleban were in government until 2001 when they were toppled in a US-led offensive.
Nato fears that Taleban violence will escalate in several areas of Afghanistan as the winter snows thaw.
Nato commanders have said they need more soldiers to tackle the expected spring offensive.