Afghan officials voiced concern over the deteriorating security situation in western Afghanistan, after a district there was briefly captured by the Taliban.

Security forces on Monday retook the Anar Dara district's police and administrative offices from Taliban fighters, after troop reinforcements launched an air and ground operation that lasted several hours.

At least eight members of the Afghan security forces were killed, including the district police chief, officials confirmed.

"Such attacks by the Taliban can happen over and over again," Farid Bakhtawar, head of the provincial council, told Al Jazeera. "The security situation here is getting worst and it is of a major concern at the moment."

About 300 fighters attacked the police headquarters early on Monday with the Taliban immediately claiming responsibility, saying the district was under their control.

The attack took place hours after the fighters killed seven members of the army and eight policemen in Bala Buluk district in the province.

On Tuesday, at least five Afghan police forces were killed and five others kidnapped in an attack near a checkpoint in Farah city.

Although none of the areas in Farah province are under Taliban control, Bakhtawar said the fighters repeatedly managed to take over district headquarters, and at times, also manage to enter the provincial capital, Farah city.

According to a recent BBC study, the Taliban are active in 70 percent of districts in Afghanistan, fully controlling four percent of the country, and demonstrating an open physical presence in another 66 percent.

Taliban as 'political party'

There was no official response from the Taliban to president of Afghanistan Ashraf Ghani's invitation last month to unconditional talks.

One of the key points of the peace plan announced by Ghani was to recognise the Taliban as a political party.

The Taliban however invited US officials to its political office in Qatar to discuss a "peaceful solution" to end the bloodshed in Afghanistan.

The group also said that departure of American troops from Afghanistan remains a precondition for the group's talks offer.

But Jim Mattis, the US defence secretary, said on Tuesday during an unannounced visit to Kabul that the elements of the Taliban are open to talks with the Afghan government.

In December, General John W Nicholson Jr of the US army said his country would deploy more troops in an advisory role to Afghan forces in 2018, on top of the 14,000 American soldiers already stationed in the country.

The increase follows Trump's pledge in August 2017, saying the US will continue to fight armed groups in Afghanistan.

"We are not nation building again. We are killing terrorists," Trump said.

The US invaded Afghanistan in 2001, in what has become the country's longest military intervention since Vietnam. It has also been the costliest, with more than $100bn spent so far.