KABUL, Afghanistan — The Taliban ambushed and killed the director of Afghanistan’s government media center on Friday in the capital, Kabul, the latest killing of a government official just days after an assassination attempt on the country’s acting defense minister.

The slaying comes amid significant Taliban advances. In a major but symbolic victory, the Taliban on Friday appeared to have taken their first provincial capital — the city of Zaranj in southern Nimroz province. The government, however, claimed there was still fierce fighting around key infrastructure in the city and that Zaranj had not fallen.

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’s mainly desert and Zaranj, the provincial capital, has about 50,000 residents. The province’s governor, Abdul Karim Barahawi, fled Zaranj for refuge in the peaceful Chahar Burjak district, where the local ethnic Baluch population has given him protection.

The Taliban have been surging for months in Afghanistan, taking swaths of land as U.S. and NATO forces complete their final pullout from the country by the end of the month. The battles intensified lately as the Taliban laid siege to provincial capitals in southern and western Afghanistan, after capturing district after district and even seizing several key border crossings.

Menapal Gunned Down in His Car By ‘Holy Warriors’

Taliban spokesman Zabihullah Mujahid told The Associated Press 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 in Kabul, according to the Interior Ministry’s deputy spokesman, Said Hamid Rushan. After the shooting, Afghan forces fanned out across the neighborhood where Menapal was gunned down while riding in his car. Mujahid put out a statement claiming responsibility and said 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 targeted the acting defense minister, Bismillah Khan Mohammadi. The attack in a heavily guarded upscale Kabul neighborhood late Tuesday killed at least eight people and wounded 20. The minister was unharmed. The bombing was followed by a gunbattle 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 U.S. Air Forces Fire Airstrikes at Taliban Positions

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

Residents in Helmand’s contested provincial capital, Lashkar Gah, said airstrikes destroyed a market in the center 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.

Afghanistan’s elite commandos have deployed to Lashkar Gah, backed up by airstrikes by the Afghan and U.S. air forces.

The Taliban began sweeping across Afghanistan at an unexpected speed after the U.S. and NATO began their final pullout in late April. The bitter fighting has displaced hundreds of thousands of Afghans, now living in miserable conditions in improvised shelters and makeshift camps in the southern, desert-like environment — brutally hot days and cold nights. Inside the cities where fighting is underway, thousands are trapped and unable to move from their homes.

Fighting Leaves Residents Without Proper Food and Shelter

In the southern city of Kandahar, the capital of the province with the same name, hundreds are sheltering in makeshift camps, wondering where they will get food for their children. In Lashkar Gah, the shuttered office of Action Against Hunger, a global humanitarian organization, was hit in an airstrike on Thursday, the group said in a statement. Fighting had forced the organization to close its office last week.

More than half of Afghanistan’s 421 districts and district centers are now in Taliban hands. While many of the districts are in remote regions, some are deeply strategic, giving the Taliban control of lucrative border crossings with Iran, Tajikistan and Pakistan.

At a special meeting at the U.N Security Council on Friday, Deborah Lyons, the U.N. envoy to Afghanistan, said the human toll of the worsening fighting was deeply disturbing.

“The war in Afghanistan has entered a new, deadlier, and more destructive phase,” she said. “The provincial capitals of Kandahar, Herat, and Lashkar Gah in particular have come under significant pressure. This is a clear attempt by the Taliban to seize urban centers with the force of arms.”

“The human toll of this strategy is extremely distressing — and the political message is even more deeply disturbing,” she said, adding that in just 10 days in Lashkar Gah, 104 civilians were killed. Lyons appealed on the council to send a strong signal “that it is essential to stop fighting and negotiate, in that order.”

“Otherwise, there may be nothing left to win,” she said.

Taliban Takes Control of Afghanistan’s Border Crossing

In southeastern Afghanistan, the Taliban last month took control of the town of Spin Boldak on the border with Pakistan, one of Afghanistan’s busiest border crossings. Thousands of Afghans and Pakistanis cross daily and a steady stream of trucks passes through, bringing goods to land-locked Afghanistan from the Arabian Sea port city of Karachi in Pakistan.

The Taliban shuttered the crossing Friday over a visa dispute, claiming Pakistan was abiding by Kabul government requirements for Afghans traveling into Pakistan to have a passport and a Pakistan visa. Previously, travel documents were rarely demanded and Afghans with local ID card could cross into Pakistan.

“The border will stay closed until Pakistan allows all Afghans to cross on the bases of our old procedure,” said a Taliban statement.

At the border, traders said about 1,500 people were waiting on both sides Friday to pass through. More than 600 trucks, many loaded with perishable fresh foods, were backed up in both countries.

Islamabad’s relationship with Kabul has been deeply troubled with both sides accusing each other of harboring militants. Afghan Taliban leaders live in Pakistan and Kabul is bitterly critical of Pakistan for aiding them and treating their fighters in hospitals in Pakistan. Islamabad meanwhile charges that Kabul provides a safe haven to the Pakistani Taliban, a separate militant group that regularly stages attacks in Pakistan.