Najib Danish, spokesman for the Interior Ministry, said at least six security forces were killed and 12 others, including the deputy provincial police chief, were wounded in the attack.
Gen. Raz Mohammad Oryakhel, the commander for 207Zafar Military Corps, told Pajhwok Afghan News that militants launched a coordinated attack on the capital of Farah on 2am last night and entered parts of the city on 5pm Monday morning.
Islamic State claimed responsibility for the attack, in a busy area of the city with many other official buildings nearby, including a school in which about 1,000 girls were trapped as the fighting raged.
"I can say that it is street-to-street battle", a city official, Mohammed Sarwar Usmani, told Arab News.
Bakhtawer said casualties were high among security forces, but could not provide a precise number.
During this time, Kohistan district in Badakhshan province, Belchiragh district in Faryab province and Tala Wa Barfak district in Baghlan province have fallen to the Taliban.
The assault began around midnight, with the militants capturing one urban district and parts of another, said local provincial council member Jamila Amini.
The Afghan Defense Ministry said in a statement Tuesday that Afghan security forces were able to repel their attacks.
Disney parade float bursts into flames
Within minutes, a Disney employee with a fire extinguisher doused the flames. They added that operations remained normal throughout the rest of the park.
"The situation is very bad", Satar Hussaini, a tribal elder in Farah, told AFP earlier.
Another provincial council member, Dadullah Qani, confirmed Hissaini's comments, the sound of gunfire and explosions audible as he spoke to an AFP reporter by telephone.
Earlier in May, Taliban fighters attacked Afghan bases in the province, killing more than 40 police officers and servicemen.
The insurgents in a statement warned residents to remain in their homes and "stay calm".
Farah is a vast and sparsely populated province with tens of thousands of dollars generated under custom duty.
Despite security concerns, the Taliban have pledged to cooperate with the gas project.
At least some militants have been hiding in residential houses, making it hard for Afghan forces to use heavy weapons, Farah Governor Abdul Basir Salangi told Ariana News, adding: 'But still we are taking back positions one by one'.
After several hours of fighting that sent plumes of smoke rising into the sky above the accounts office, Attahullah Khogyani, a spokesman for the provincial governor, said that Sunday's clash had ended with all the gunmen killed. Kunduz was subsequently retaken by the government both times.