"We had intelligence reports that suicide bombers were planning to attack Qala-i-Naw," Badghis governor Abdul Ghafoor Malikzai told AFP. "The attackers took over a building near the governor's office and police headquarters".
The defence ministry said three attackers were killed and two more arrested.
Four members of the Afghan security forces were killed and 20 people wounded, including civilians, the ministry said.
The incident comes less than a week after Taliban officials were sitting face-to-face with US negotiators in Doha in a bid to end Afghanistan's nearly 18-year-old war.
Meanwhile a US service member was killed in action in Afghanistan on Saturday, NATO said, in a Taliban-claimed attack that comes as America tries to forge a peace deal with the insurgentsThe soldier is the 10th member of the US military to be killed this year - compared to 12 in all of 2018.
"The name of the service member killed in action is being withheld until 24 hours after notification of next of kin is complete," Resolute Support, the US-led NATO mission in Afghanistan, said in a statement. NATO did not provide any details about the incident for which the Taliban claimed responsibility.
Both sides reported good progress in the talks, but daily carnage continues across Afghanistan and NATO on Saturday announced the death of a US service member who was killed in a Taliban-claimed attack.