Officials in eastern Afghanistan say a suicide truck bomb has killed four police officers and wounded 17 people.
Authorities say the suicide attack took place Monday outside the Nirkh district police headquarters in Wardak province, southwest of Kabul, the Afghan capital.
The Taliban claimed responsibility for the assault.
Afghan insurgents have increased their attacks in a campaign to retake territory as foreign forces withdraw.
Suicide attacks and roadside bombs are the militants' favored weapons, but they often result in civilian casualties.