KABUL, Afghanistan — The Taliban have captured the capital of one of Afghanistan’s western provinces, Afghan officials said on Friday, a symbolic milestone in the insurgents’ relentless march to retake power in the country.
Zaranj, the provincial capital of Nimruz on the Afghanistan-Iran border, has collapsed and is now in the hands of the insurgents, according to Rohgul Khairzad, the deputy governor of Nimruz, and Haji Baz Mohammad Naser, the head of the provincial council.
It is the first provincial capital to be captured by the insurgent group since the Biden administration said it would completely withdraw American troops from Afghanistan by next month. The Taliban have besieged a host of such cities for weeks, and the likely fall of Zaranj, a city of 160,000 people, is the Taliban’s first major breakthrough.
The city’s collapse occurred on the same day that a senior government official was assassinated in Kabul, the capital. It also came as the insurgents pressed hard into other provincial cities, in a day of bleak news for the government.
“All the people are hiding in their houses in fear of the Taliban,” said Khair-ul-Nisa Ghami, a member of the provincial council. “The situation is very worrying. People are scared,” she said, adding: “The Taliban captured the city without any fighting.”
Mr. Naser, the provincial council head, said that the government had failed to send reinforcements to Zaranj, and that officials had decided to abandon the city in order to avoid casualties. He denied that a deal had been struck with the Taliban.
Situated in the remote southwestern corner of the country, Zaranj is Afghanistan’s main hub for illegal migration. For decades, a steady flow of Afghans displaced by conflict and poverty have flocked to the city’s smuggler-owned hotels and brokered deals to cross through the mountains into Iran.
Since the Taliban began its military campaign in May, the city has buzzed with people looking to leave the country. In early July, around 450 pickup trucks carrying migrants snaked from Zaranj toward crossing points along the Iranian border each day — more than double the number of cars that made the trip in March, according to David Mansfield, a migration researcher with the British Overseas Development Institute.
The seizure of Zaranj is a symbolically significant development in the Taliban’s campaign, as they have moved away from targeting rural districts to focus on attacking provincial capitals.
The 215th Corps of the Afghan National Army is responsible for security in both Zaranj and Lashkar Gah, the capital of neighboring Helmand Province, which has been under siege for several days. The 215th Corps’ leadership had shifted its focus to defending Lashkar Gah, leaving Zaranj vulnerable to capture.
The Taliban also took responsibility for the assassination on Friday of a senior government official in Kabul. Dawa Khan Meenapal, the head of the government’s media and information center, was gunned down in a targeted attack.
The assassination came days after a coordinated attack by the insurgent group on the residence of the acting defense minister that left eight people dead. That assault highlighted the Taliban’s ability to strike in the heart of the Afghan capital as they continue their sweeping military campaign.
In northern Afghanistan on Friday, the Taliban attacked another provincial capital, Sheberghan, from five directions, burning houses and wedding halls, and assaulting the police headquarters and the prison. There were numerous civilian casualties, said Halima Sadaf Karimi, a member of Parliament from Jowzjan Province, of which Sheberghan is the capital.
Fighting also continued around the major western city of Herat, in Kandahar city in the south and in other provincial capitals.
The government’s response to the insurgents’ recent victories has been piecemeal. Afghan forces have retaken some districts, but both the Afghan air force and its commando forces — which have been deployed to hold what territory remains as regular army and police units retreat, surrender or refuse to fight — are exhausted.
In the security forces’ stead, the government has once more looked to local militias to fill the gaps, a move reminiscent of the chaotic and ethnically divided civil war of the 1990s that many Afghans now fear will return.
Christina Goldbaum and Thomas Gibbons-Neff contributed reporting.