The Taliban escalated its nationwide offensive in Afghanistan on Sunday, renewing assaults on three major cities and rocketing a major airport in the south amid warnings that the conflict was rapidly worsening. As Afghan government forces struggled with a resurgent Taliban after the withdrawal of US-led foreign forces, hundreds of commandos were deployed to the economically important western city of Herat, while authorities in the southern city of Lashkar Gah called for more troops to rein in the assaults amid fierce fighting. In Lashkar Gah, the provincial capital of Helmand – once the focus of UK military efforts – eyewitnesses described street fighting, bodies lying in the open and Afghan government and US airstrikes raining down on Taliban positions. According to reports from the city, Afghan forces remained in control of the city centre late on Sunday. The current focus of the Taliban’s efforts appears to be a number of key provincial capitals, not least in the country’s south, with the ambition that the fall of Kandahar or Lashkar Gah would rapidly topple the five surrounding provinces. The capture of any major urban centre would also take their current offensive to another level and fuel concerns that the army is incapable of resisting the Taliban’s advances. The spokesperson for the Afghan armed forces, Gen Ajmal Omar Shinwari, told a press conference on Sunday that three provinces in southern and western Afghanistan faced critical security situations. Aid agencies are also fearful that the fall of a major city would worsen an emerging humanitarian crisis that has already forced large numbers to flee their homes. “The aircraft are bombing the city every minute. Every inch of the city has been bombed,” Badshah Khan, a resident of Lashkar Gah, told Agence France-Presse by phone. “You can see dead bodies on the streets. There are bodies of people in the main square.” The Taliban also struck the sprawling Kandahar airport in southern Afghanistan with at least three rockets overnight, the insurgent group’s spokesman said on Sunday, adding that the aim was to thwart airstrikes conducted by Afghan government forces. “Kandahar airport was targeted by us because the enemy were using it as a centre to conduct airstrikes against us,” said Zabiullah Mujahid, a Taliban spokesperson. Afghan government officials said the rocket attacks forced authorities to suspend all flights and the runway was partially damaged. Airport chief Massoud Pashtun said two rockets had hit the runway and repairs were under way, with planes likely to resume service later on Sunday. The facility is vital to maintaining the logistics and air support needed to keep the Taliban from overrunning the city, while also providing aerial cover for large tracts of southern Afghanistan. Officials said the Taliban saw Kandahar as a major strategic focus for their efforts amid the suggestion that the Taliban would like to use it as a temporary capital in the south. In the country’s west, Afghan officials acknowledged that the Taliban had gained control of strategic buildings around Herat city, forcing civilians to remain in their homes. On Sunday, the ministry of defence said that hundreds of commandos had been sent to Herat to help beat back the insurgent assault. “These forces will increase offensive operations and suppress the Taliban in Herat,” the ministry tweeted. Lashkar Gah, however, appears the most vulnerable. Heavy clashes between the Taliban and government forces were continuing inside the city on Sunday, with militant fighters described as being only a few hundred metres from the governor’s office on Saturday amid Afghan and US airstrikes on Taliban positions. “Fighting is going on inside the city and we have asked for special forces to be deployed,” Ataullah Afghan, the head of Helmand provincial council, told AFP. “The city is in the worst condition. I do not know what will happen,” said Halim Karimi, a resident of the city of 200,000 residents. “Neither the Taliban will have mercy on us, nor will the government stop bombing.” The Taliban has been advancing in Afghanistan after the withdrawal of US and Nato troops from the country, and in recent weeks the fundamentalist Islamist group said it had captured more than half of all Afghanistan’s territory, including border crossings with Iran and Pakistan. As fighting raged, President Ashraf Ghani again slammed the Taliban for failing to marshal its negotiating power to reach a peace deal. “We want peace but they want us to surrender,” Ghani said at a cabinet meeting. The government has repeatedly dismissed the militants’ steady gains over the summer as lacking strategic value but has largely failed to reverse their momentum on the battlefield. The Taliban has seized Afghan cities in the past but have managed to retain them only briefly. The increasingly dire situation in Afghanistan has raised fears of a new Taliban takeover, with Boris Johnson admitting in the House of Commons last month that he was “apprehensive” about the future of Afghanistan. “If you ask me whether I feel happy about the current situation in Afghanistan, of course I don’t. I’m apprehensive,” Johnson told parliament’s liaison committee. Thousands have been killed in the conflict, including more than 50,000 Afghan civilians and more than 2,000 US and 400 British troops.