The Taliban has killed the director of Afghanistan’s government media centre in the capital Kabul just days after an assassination attempt on the country’s acting defence minister.

The killing comes amid Taliban advances and battles for more territory as US and Nato forces complete their final pullout from Afghanistan by the end of the month.

The Taliban have been waging fierce battles for months across Afghanistan, laying siege to provincial capitals in the south and west of the country after capturing district after district and seizing several key border crossings.

In southern Nimroz province, the capital of Zaranj appeared to be the first provincial capital to fall to the Taliban though the government claimed there was still fierce fighting around key infrastructure in the city.

But the Taliban posted images on social media showing insurgents inside the local airport and posing for photographs at the entrance to the city.

Nimroz is sparsely populated in a region that is mainly desert and Zaranj, the provincial capital, has about 50,000 residents. Its fall to the Taliban would be a mostly symbolic victory for the insurgents.

Taliban spokesman Zabihullah Mujahid said that the insurgents killed Dawa Khan Menapal, the chief of the Afghan government’s press operations for local and foreign media. He had previously been a deputy spokesman for Afghan President Ashraf Ghani.

The assassination took place during weekly Friday prayers, according to the Interior Ministry’s deputy spokesman, Said Hamid Rushan.

After the shooting, Afghan forces fanned out across the neighbourhood of Kabul where Mr Menapal was gunned down while travelling in his car.

Mujahid later put out a statement claiming responsibility and said that Mr Menapal “was killed in a special attack” by the mujahedeen, or holy warriors.

The Taliban often target government officials and those they perceive as working for the government or foreign forces, though several recent attacks have been claimed by the Islamic State group. The government most often holds the Taliban responsible.

Earlier this week, a Taliban bombing attack targeted Afghanistan’s acting defence minister, Bismillah Khan Mohammadi. The attack in a heavily guarded upmarket Kabul neighbourhood late on Tuesday killed at least eight people and wounded 20. The minister was unharmed.

The bombing was followed by a gun battle that also killed four Taliban fighters. The militants said the attack was to avenge Taliban fighters killed during government offensives in rural provinces.

Afghan and US aircraft pounded Taliban positions in southern Afghanistan’s Helmand province on Friday, as the insurgents closed a major border crossing with neighbouring Pakistan.

Residents in Helmand’s contested provincial capital, Lashkar Gah, said airstrikes destroyed a market in the centre of the city — an area controlled by the Taliban. Afghan officials say the Taliban now control nine out of the 10 districts of the city.

The bitter fighting has displaced hundreds of thousands of Afghans, now living in miserable conditions improvised shelters and makeshift camps in the southern, desert-like environment — brutally hot days and cold nights.

Inside the cities where fighting is under way, thousands are trapped and unable to move from their homes.