US aircraft conducted at least four air strikes but details of the fighting were unclear as most of the city’s telecoms masts were destroyed in fighting over recent days.

Mohammad Sharif Yaftali, Afghan army chief of staff, said the city was not under threat of collapse and heavy fighting was underway to push back the Taliban from city limits.

“Strategic locations and centers in the city are under the control of Afghan forces and the Taliban are hiding inside people’s homes and shops and resisting,” Yaftali told reporters at a news conference in Kabul, Reuters reported.

But lawmakers from Ghazni who managed to talk to some residents said Taliban were in control of much of the city after launching an initial attack in the early hours of Friday.

“Only the governor’s office, police headquarters and intelligence agency’s compound are in the hands of the government and Taliban are pushing to take them,” said Chaman Shah Ehtemadi, a lawmaker from Ghazni.

The attack on Ghazni, a strategic city on the main highway linking Kabul with Afghanistan’s south, was the most serious blow to the government since the insurgents came close to overrunning the western city of Farah in May.

Mohammad Rahim Hasanyar, a member of the provincial council, said heavy fighting was continuing in several areas of the city and Afghan forces were in defense mode.

“No one knows what the exact situation is because there is no communication service,” he said.

There was no confirmed word on casualties. Quoting a hospital official, Afghanistan’s 1TV television reported more than 90 members of the security forces and 13 civilians had been killed, with more than 100 wounded. It said there had also been heavy Taliban casualties.

With the highway heavily mined to prevent reinforcements from arriving, residents were largely blocked inside but some who managed to escape across fields on the city’s periphery said many government buildings were ablaze.

“There was burning and fire and dead bodies everywhere in the city,” said Abdul Wakil, a local resident who escaped told Reuters at a checkpoint into Kabul.

Short videos circulating on social media, purported to be from Ghazni, show a number of heavily armed Taliban patrolling in the city with a large plume of smoke and flames coming out from the town.

“It is over and the city is taken,” says a man standing outside his home, with several Taliban insurgents nearby.

The videos could not be independently verified but they generated heavy commentary by social media users that underlined the shock caused by the attack.

US military headquarters in Kabul said sporadic clashes were occurring and American aircraft had conducted five strikes on Saturday and four more on Sunday.

“The Afghan National Defense and Security Forces continue to hold their ground and maintain control of all government centers,” Lt Col Martin O’Donnell, US Forces Afghanistan spokesman, said in an emailed statement.

The attack on Ghazni leaves the future of peace talks with the Taliban uncertain. The government had been considering a ceasefire over this month’s Eid al Adha holiday to match a similar truce during June’s Eid al Fitr holiday.