The Taliban claim they have taken control over the city of Sheberghan, a north Afghan province of Jawzjan.
Afghan Defense Ministry spokesman told the BBC that government forces were still in the city and would clear out the Taliban “soon”.
For the second time in recent days, a regional capital has fallen to the militants.
The first occurred on Friday when Zaranj in the south-western province of Nimrozfell also fell into the militant’s hands.
In a major blow to the country’s security forces, battles have raged across the country.
As the fighting intensifies, many areas in Afghanistan are left without any hope of peace.
There are also reports of heavy fighting in Kunduz in the north of Afghanistan and the city of Lashkar Gah in the south.
The withdrawal of international forces has led to an increase in violence across Afghanistan.
The United States and other countries involved have been gradually pulling out troops from this country following 20 years of military operations.
The Taliban have been making unprecedented advances in their fight to take over Afghanistan.
Recent weeks have seen the militants capture large swathes of territory across the country and now they are targeting key towns and cities.
Sheberghan is a stronghold of the former Afghan vice-president and warlord, Abdul Rashid Dostum, whose supporters have been leading the fight against the insurgents.
In a move to counter the recent Taliban insurgence, reports from the local media suggest that 150 people have travelled to the city to assist the Afghan forces.
The Taliban stormed the governor’s compound on Friday, and at one point it was captured. But Afghan security forces were able to retake their position in a short time span”.
Afghan security forces were able to retake the governor’s compound from Taliban militants who seized control on Friday.
However, the region’s council chief, Babur Eshchi, told the BBC that militant forces now control the whole city except for an army base.
He went on to say that fighting is still going on at this time.
Afghan defence ministry spokesman Fawaad Aman told the BBC’s Newshour programme that government forces were still in “the majority” of Sheberghan, including the airport. He insisted they would be “clear of terrorists soon”.
But he conceded the Taliban had captured some parts of the city, and that government troops retreated to save civilian casualties.
The Afghan defence ministry has announced that US B-52 bombers have successfully hit Taliban positions in the city.
Taliban officials meanwhile said they had taken a prison in Sheberghan, and footage on social media shows the release of hundreds of inmates leaving the city jail.
The provincial capitals of Herat in the west, and the southern cities of Kandahar and Lashkar Gah are also under pressure.
The Afghan military says dozens of Islamist fighters, including senior commanders, have been killed in Lashkar Gah, however the Taliban has denied these claims.
The Afghan capital Kabul was shaken by violence once again this past week with two major incidents occurring.
The Taliban shot dead President Ashraf Ghani’s former spokesman and carried out a bomb attack on the house of the acting defence minister.
In recent weeks, Taliban fighters have also captured key border crossings with neighbouring countries.
The militant group has closed the border with Pakistan and dozens of Afghans can be seen stranded on the Pakistani side, unable to return home.
A man trying to get home to Kandahar told Reuters news agency:
“We came to Pakistan to attend a funeral three days ago. Now the border is closed. We’re sitting here. We have no food and no money”.
The UK and US governments are urging their citizens to leave the country immediately because of the worsening security situation and threats against its nationals.
The British Foreign Office released a statement on Friday that warned militants are likely to carry out attacks in Afghanistan.
The US has announced that citizens can receive a repatriation loan if they cannot afford to pay for commercial flights themselves.
