Jalandar Shah Behnam, the army commander, told the AFP news agency that Afghan soldiers and police and troops from Nato's International Security Assistance Force (Isaf) surrounded on Wednesday the Taliban's compound in the Bala Buluk district.
In initial fighting two Afghan soldiers and a policeman were killed and several others wounded.
"Later, Isaf aircraft bombed the fort and 30 Taliban including their ranking commanders were killed," Behnam said.
"There is no one left inside the fort."
Mohammad Nabi Popal, Farah's deputy police chief, said 30 Taliban members were killed along with one policeman.
"They were mostly Taliban from Helmand and some Pakistani Taliban who infiltrated our province from neighbouring Helmand province," he said.
Popal said on Thursday that Isaf jets also bombed another area of Farah overnight after the Taliban attacked police, wounding three of them.
|Thursday's suicide bombing in Kabul |
killed three Afghan civilians [AFP]
"Heavy casualties were inflicted to the Taliban but we don't have confirmed figures," he said.
Popal said "up to 15 may have been killed".
Isaf did not immediately comment.
The Nato force has been carrying out intense operations in Helmand over the past weeks, saying it has caused significant losses to the Taliban, particularly in the Garmser district on the border with Pakistan.
In Thursday's Kabul attack, a suicide a bomber targeted a vehicle carrying foreigners on Thursday, killing three Afghan civilians, police said.
"There has been a suicide attack against foreigners," Alishah Paktiawal, Kabul's police chief, said, without giving casualty figures.
A policeman at the scene said three Afghans were killed in the blast - two youngsters and a lorry driver.