The attack comes amid of a flurry of suicide attacks, roadside bombings and shootings that have claimed lives across the country.
About 400 Taliban fighters in 35 trucks arrived in Bakwa, a town in southwestern Farah province, late Sunday and launched a heavy assault on the district police and administration headquarters.
The fighters fled back towards neighbouring Helmand province after a five-hour battle, carrying an unknown number of casualties with them.
Also in Farah, four suspected suicide attackers riding on two explosive-laden motorbikes were killed after they were challenged by police as they drove through the provincial capital late Sunday, said Gen. Sayed Aga Saqib, provincial police chief.
Saqib said two of the suspected attackers were shot dead by police, while the other two were killed when police shot at their bike and detonated their explosives.
A boy passer-by also was killed in the explosion, while the child's father was wounded.
A remotely-detonated car bomb seriously wounded two US-led coalition soldiers in the Daman district of southern Kandahar province on Monday .
Maj. Scott Lundy, a coalition spokesman, said a van appeared to have broken down on the road then exploded as a patrol passed.
The coalition declined to reveal the wounded soldiers nationalities or identities.
Lundy said their conditions were "serious but not life-threatening."
In eastern Afghanistan, an attacker traveling in a taxi from neighbouring Pakistan exploded two grenades at a border police checkpoint in Khost province late Sunday, killing a civilian and wounding three others, police said.
In western Ghor province, gunmen killed a doctor and a driver working for the aid agency World Vision.
The two Afghans were driving back to Chaghcharan from the town of Charsada, where they had delivered medicine, said Karimuddin Razazada, deputy governor of Ghor province.
It was not immediately clear who was responsible for the attack.