Timeline: Taliban's swift military campaign across Afghanistan

KABUL: Less than a week after US-led foreign forces pulled out of Afghanistan, the Taliban have managed to take over more than a quarter of Afghanistan's 34 provincial capitals. 

Here is a look at the three months since the Taliban's sweeping offensive in Afghanistan began: 

Fierce fighting

In early May, the North Atlantic Treaty Organization (NATO) began a final withdrawal of its mission in Afghanistan involving 9,600 soldiers — 2,500 of them American.

Following the withdrawal, intense fighting broke out between the Taliban and government forces in southern Helmand province.

A bomb blast outside a girls' school on May 8 in Kabul killed 85, mostly young students. 

The deadliest attack in a year is blamed on the Taliban, however, they do not take responsibility for it. 

Taliban advances

In mid-May, the US forces withdrew from one of Afghanistan's largest air bases in Kandahar, the country's second-biggest city. 

The insurgents then seized districts in Wardak province near Kabul, and in the key province of Ghazni, which straddles roads connecting the capital to Kandahar.

By mid-June, the Taliban had managed to capture several districts in northern provinces, forcing military retreats.

On June 22, the Taliban took control of the main Shir Khan Bandar border crossing with Tajikistan, prompting the Central Asian country to check the combat readiness of its armed forces.

US leaves Bagram

Officials on July 2 announced the departure of all American and NATO troops from Bagram, Afghanistan's biggest airbase, which served as the linchpin of US-led operations in the country for two decades.

Two days later, the Taliban seize the key district of Panjwai in Kandahar, the insurgents' birthplace and former bastion.

On July 9, the Taliban announced the capture of Islam Qala, Afghanistan's biggest border crossing with Iran. 

On July 14, the insurgents took control of the Spin Boldak border crossing with Pakistan, a major trade route between the two countries.

Urban onslaught

From then onwards, the Taliban offensive escalated sharply with a new focus on urban centres as the insurgents attacked the cities of Lashkar Gah, Kandahar, and Herat.

The United States and Britain say that the Taliban may have committed war crimes, accusing the insurgents of "massacring civilians" in the town of Spin Boldak.

On August 3, eight people are killed in a coordinated bomb and gun attack targeting the Afghan defence minister and several lawmakers in Kabul. The Taliban claim this attack. 

On August 6, the Taliban shoot dead the head of the Afghan government's media information centre at a mosque in the capital, Kabul.

Provincial capitals fall

The Taliban capture their first Afghan provincial capital, the city of Zaranj in southwestern Nimroz, taking it "without a fight".

The following days several other northern cities fall, Sheberghan, Kunduz, Sar-e-Pul, Taloqan, Aibak, Farah and Pul-e-Khumri.

Despite the bloodshed and sweeping advances, US President Joe Biden gives no suggestion that he will delay the withdrawal deadline.

On August 11, Afghan President Ashraf Ghani flies to the besieged northern city of Mazar-i-Sharif to rally his forces.

Ashraf Ghani's visit is, however, overshadowed by the surrender of hundreds of Afghan soldiers in nearby Kunduz and the overnight capture of a ninth provincial capital, Faizabad.

Within reach of Kabul

On August 12, the Taliban capture Ghazni, 150 kilometres (90 miles) southwest of Kabul. 

Herat falls in the west on the same day, and a day later the Taliban capture Kandahar and Lashkar Gah in the south.

The cities of Asadabad and Gardez fall on Saturday with Mazar-i-Sharif, which President Ghani had visited just three days earlier.

Jalalabad is taken over by the insurgents early on Sunday, leaving Kabul the only remaining major Afghan city still under government control.