The Taliban seized near total control over another provincial capital in northern Afghanistan on Monday, local and security officials said, a day after the insurgent group took three others, including the strategic and economically important city of Kunduz.
It is the sixth provincial capital to have fallen in a matter of days as Taliban forces, emboldened by the departure of U.S. troops from the country, have sped up their campaign across Afghanistan.
Fighting on the outskirts of Aybak, the capital of Samangan Province, began on Monday morning as the Taliban pushed into the city, having toppled a nearby district two days earlier. By the afternoon, most of the city was under insurgent control, and most government forces had fled.
“Aybak fell to the Taliban, and all officials and security forces retreated,” said Assadullah, a dispatcher at Samangan Police headquarters who uses just one name. “Now I am hiding in the city.”
Raaz Mohammad Mowahid, a member of the Samangan provincial council, said that the city had collapsed but that there had not been much fighting between government troops and the Taliban.
“Security forces retreated to a mountain to the south,” Mr. Mowahid said.
Aybak sits on the main highway that connects Kabul, the country’s capital, to Afghanistan’s northern provinces. The city’s fall means that the Taliban have effectively placed a stranglehold on much of Balkh Province and its immensely important capital, Mazar-i-Sharif.
Nazir Ahamad, a cellphone seller in the city, said that the Taliban had seized all of the government buildings in Aybak and that shops were closed. Hundreds of prisoners were also released from the jail.
“The Taliban entered without a gunshot,” he said.
Contributing to the collapse of the city on Monday was the defection of a former member of Parliament and prominent militia commander who joined the Taliban, bringing hundreds of fighters with him, two officials said. The move spread panic in the Afghan forces ranks as Taliban fighters closed in.
The insurgent group’s rapid expansion and seizure of important urban centers across the north has put the Afghan government in a tenuous position.
Resupply lines to government forces are severed, and the cities and districts still under the government’s control — long considered islands under threat by the Taliban — are even more cut off and isolated.
Now, the Afghan government must decide whether to reconstitute its forces around the territory it holds — including Kabul, which could soon come under attack — or try to retake their fallen cities.
On Monday, fighting was continuing on the outskirts of Mazar-i-Sharif and inside the provincial capital of Baghlan, another important province to the southeast of Samangan.
U.S. airstrikes in support of the Afghan forces have been muted and prominently concentrated away from the north. On Sunday, as Afghan troops reeled from their defeats, it was clear that the United States was not coming to their rescue.