Thousands of panicked people mobbed the airport in Kabul on Monday trying to flee the feared hardline rule of the Taliban, who were once again in control of Afghanistan in a stunningly swift end to 20 years of war.
At the airport, frantic Afghans tried to board the few flights available throughout the day, before US forces - sent in to secure the facility - shut down military and civilian operations.
"We are afraid to live in this city," a 25-year-old ex-soldier told the AFP news agency as he stood among huge crowds on the tarmac.
"Since I served in the army, the Taliban would definitely target me."
The airport reopened in the early hours of Tuesday, a US general said, adding that US personnel were now in charge of air traffic control.
Dramatic footage posted on social media showed hundreds of men running alongside a US Air Force plane as it rolled down the runway, with some clinging to the side of it.
Thousands of Afghans rush to the Hamid Karzai International Airport as they try to flee the Afghan capital of Kabul, Afghanistan, on August 16, 2021. Source: Anadolu
In other videos, civilians frantically clambered up an already overcrowded and buckling jetway.
US soldiers shot dead two men in the crowd with weapons who had "brandished them menacingly", a Pentagon official said.
The US - which was left shocked by the rapid collapse of the Afghan government - has sent 6,000 troops to ensure the safe evacuation of embassy staff, as well as Afghans who worked as interpreters or in other support roles.
Other governments including France, Germany and Australia have also organised charter flights.
Meanwhile, US President Joe Biden has defended his troop pullout from Afghanistan after several days of silence on the momentous developments.
He said he stood by the policy and that it was time to leave after 20 years of conflict.
"I am president of the United States of America and the buck stops with me," Mr Biden said in a much-awaited televised address from the White House.
He said he was "deeply saddened" by the turn of events - and promised to "speak out" on the rights of women now facing a return to Taliban rule.
Mr Biden acknowledged that the Afghan government collapsed more quickly than he expected - and suggested that they had lacked the will to stand up to the Taliban.
The militants captured Kabul, and many other cities, with little bloodshed - but in the capital, a sense of panic and fear has overwhelmed residents, some of whom are worried about a repeat of the insurgents' brutal Islamist rule from 1996 to 2001.
'Time to test and prove'
Taliban fighters have taken over checkpoints across Kabul, and militants with rifles slung over their shoulders walked through the streets of the Green Zone, the heavily fortified district that houses most embassies and international organisations.
Afghan President Ashraf Ghani fled the country on Sunday, finalising the collapse of his government which, without the support of the US military, was unable to withstand the Taliban assault.
"The Taliban have won with the judgement of their swords and guns, and are now responsible for the honour, property and self-preservation of their countrymen," Mr Ghani said afterwards.
The Taliban sought to reassure the international community that Afghans should not fear them, and said they will not take revenge against those who supported the US-backed alliance.
"Now it's time to test and prove. Now we have to show that we can serve our nation and ensure security and comfort of life," Taliban co-founder Abdul Ghani Baradar said in a message posted to social media.
He called on his fighters to remain disciplined following their victory, which capped a 10-day lightning offensive across the country.
The US military invaded in 2001 after the September 11 attacks and toppled the Taliban for its support of Al-Qaeda.
But in the 20 years since, the United States ultimately failed to build a democratic government capable of withstanding the insurgent onslaught.
Mr Biden - who was facing criticism for the manner in which he orchestrated the US withdrawal from Afghanistan - was due to speak about the chaotic situation from the White House.
'The world is watching'
Critics say the US reputation as a global power has been badly tarnished.
German Chancellor Angela Merkel said the US-led NATO operation in Afghanistan "has not been as successful and has not been achieved in the way that we had planned".
Britain's Defence Secretary Ben Wallace described the Taliban takeover as a "failure of the international community", assessing that the West's intervention was a job only half-done.
The US government has insisted in recent days that its two decades of war in Afghanistan was a success, defined by quashing the Al-Qaeda threat.
Mr Biden said at the weekend that there was no choice but to withdraw American troops and he would not "pass this war" on to another president.
The United Nations Security Council said on Monday the international community must ensure Afghanistan does not become a breeding ground for terrorism under the Taliban, following an emergency meeting in New York.
"The following days will be pivotal," UN Secretary-General Antonio Guterres said. "The world is watching. We cannot and must not abandon the people of Afghanistan."
The United States released a statement along with more than 65 nations urging the Taliban to let Afghans leave the country, warning of accountability for any abuses.
Afghan people sit as they wait to leave the Kabul airport in Kabul on 16 August, 2021. Source: AFP
The Taliban imposed an ultra-strict interpretation of sharia law during their 1996-2001 rule. This included banning girls from schools and women from working, while people were publicly stoned to death for adultery.
China was the first major nation to flag support for the Taliban, stating it was ready for "friendly relations".
Russia's ambassador to Afghanistan planned to meet with the Taliban on Tuesday, with recognition to be determined on how they govern the country in the near future, a foreign ministry official in Moscow said.
Iran said the "defeat" of the United States would offer a chance for "lasting peace" in Afghanistan.
