The Taliban have claimed a huge symbolic victory after their fighters seized a large city for the first time in northern Afghanistan as part of a seemingly unstoppable offensive in which they have captured five provincial capitals in just three days. Armed men swept into Kunduz on Sunday, a strategic city close to the border with Tajikistan and an important political and military hub. By mid-morning they controlled the city centre while pro-government forces retreated to the nearby airport. Residents fled as smoke from the city’s burning market engulfed the sky. Videos posted by Taliban fighters showed the city’s abandoned police compound, complete with cars and its main security and intelligence buildings intact. “The enemy left behind vehicles, weapons and equipment,” tweeted the Taliban’s spokesperson, Zabihullah Mujahid, promising further advances. On Sunday, the Taliban also overwhelmed the provincial capital of Sar-e Pol and the city of Taloqan. Before communications in Taloqan were cut off, a senior local official spoke of intense street-to-street fighting. “Taliban fighters are some 200 meters away,” the official said. “It is possible that the city will fall as the security forces could not hold the lines. No help arrived from Kabul yet.” Officials later confirmed the city had been captured by the Taliban. Of the five provincial capitals to have fallen since Friday, the northern city of Kunduz was by far the most significant gain for the Taliban. Previously, the insurgents entered the city in 2015 and again in 2016, but were unable to hold it either time. Kunduz was also the scene of the Taliban’s surrender in 2001, when its northern army together with foreign fighters abandoned their weapons in the wake of the US-UK led invasion. The Biden administration’s decision in May to withdraw American troops two decades on from what it regards as an unwinnable war, prompted a precipitous collapse in security and a rampant Taliban offensive across the country. “Kunduz provincial capital fell into the hands of Taliban at around 10am this morning,” a local official said by phone. “Kunduz city has been under Taliban attack for the past two months. They intensified their attacks from several directions on the city on Friday. They totally captured it today.” According to the official, the Taliban began their main attack at about 5am on Sunday after the insurgents received reinforcements from neighbouring areas including Jawsjan province. The Taliban captured Sheberghan, the provincial capital of Jawzjan province on Saturday. The city was a stronghold of the notorious Afghan warlord Abdul Rashid Dostum. On Friday, the Taliban overran the south-western financial hub of Zaranj. “The heaviest clashes were for the intelligence and police headquarters and local governor compound,” another local official in Kunduz said. “The security officials fought with them, and then retreated toward the airport. Several bodyguards of the local governor were killed when the compound was hit by mortars.” The Taliban have seized control of much of rural Afghanistan since international forces began the last stage of their withdrawal in early May. The Taliban are now besieging more than a dozen more provincial capitals. A spokesman for the Taliban’s political office told Al Jazeera on Sunday that there was no agreement on a ceasefire with the Afghan government, and warned against further US intervention in the country. Government forces withdrew on Sunday from Sar-e Pol, the capital of a northern province of the same name. Security forces along with the local police commander and governor retreated to an army post on the outskirts. By afternoon, this was under heavy Taliban fire. The insurgent group posted video claiming the situation inside the city was now back to normal. “Sar-e Pol city fell to the Taliban this morning and now it’s under Taliban control. They now have control over the wider Sar-e Pol province,” a local said. “The local police commander and governor along with some forces have retreated to an army post in the outskirts of the city, which is also under Taliban attack now. We are now concerned about the situation of people in the city.” “They [the Taliban] started their assault on the city last night. The attack came from several directions. They overran the provincial capital at around 9am this morning. The very first thing they did was to break into the prison and release the inmates,” the official said. With most US and other western soldiers now gone, the Pentagon has sought to halt the Taliban’s advance using air power. The defence ministry in Kabul confirmed that the US launched airstrikes on Saturday night to support the beleaguered Afghan military in the city of Sheberghan. “The Taliban was targeted by a B-52 in Sheberghan city, Jawzjan, at 6.30pm on Saturday. The terrorists have suffered heavy casualties as a result of a US air forces airstrike,” said Fawad Aman, the deputy spokesman for the defence ministry. Local residents in Kunduz and Sar-e Pol said the insurgents were freely patrolling with captured Humvees in downtown areas and that many people had already fled. Latif, a resident, said: “The situation in Sar-e Pol city is devastating. There were heavy clashes overnight and in the morning we had a new ruler. They took over the city in the morning and are now freely riding on their motorbikes in the city. People are terrified. I can tell you that half of the city’s population had already fled their homes. Some people are out. There is sporadic gunfire in this corner of the city.” In Kunduz, residents said several shops caught fire after they were targeted by mortars. One, Jamal, said: “The entire city of Kunduz is burning at this moment. Many shops caught fire and a shadow of panic and fear hangs over the city. Many people fled to other areas, even to areas under Taliban control to escape from the war. Most families have one member remaining in their house to look after the properties.” Fighting also continued elsewhere in Afghanistan as Taliban combatants advanced towards the provincial capital of Samangan on Sunday afternoon. Intense fighting was also under way in parts of the economically important western city of Herat on Saturday night.