An Afghan official says a roadside bomb struck a vehicle in the western Farah province, killing five civilians, including two women and a small child.
Mohammad Naser Mehri, spokesman for the provincial governor, says four others were wounded in Wednesday's blast.
Elsewhere in Afghanistan, gunmen attacked an education department building in the eastern Nangarhar province, killing two people.
Attahullah Khogyani, spokesman for the provincial governor, said another seven people were wounded in the attack in Jalalabad, the provincial capital. He says Afghan security forces are battling the attackers.
It was not immediately clear who was behind the attack, but both the Taliban and an Islamic State affiliate are active in Nangarhar.