Five people were killed in chaos at Kabul airport on Monday, witnesses told news agency Reuters, as U.S. troops guarded the evacuation of embassy staff a day after the Taliban seized the Afghan capital and declared the war was over and peace prevailed.

It was not immediately clear how the victims died. A U.S. official said troops had fired in the air to deter people trying to force their way onto a military flight that was set to take U.S diplomats and embassy staff out of the fallen city.

One witness, waiting for a flight out for more than 20 hours, said it was unclear if the five had been shot or killed in a stampede. U.S. officials at the airport were not immediately available for a comment.

Three bodies could be seen on the ground near what appeared to be an airport side entrance, in video posted on social media. Reuters could not verify the footage. Another witness said he had also seen five bodies.

Earlier, the US said it would deploy 6,000 troops at the vital airport to ensure the safe departure of American citizens and its allies from Afghanistan which has been taken over by the Taliban, in a sudden and unprecedented collapse of the elected regime led by embattled President Ashraf Ghani.

The Taliban insurgents swept into Afghanistan's capital on Sunday after the government collapsed and president Ghani joined fellow citizens and foreigners to leave the country.

US Secretary of State Antony Blinken made a series of calls to his counterparts of US' key allies. India was not among them.

Simultaneously, more than 60 countries led by the US and the European Union issued a joint statement, urging those in positions of power and authority across Afghanistan to bear responsibility and accountability for the protection of human life and property, and for the immediate restoration of security and civil order.

"At present, we are completing a series of steps to secure Hamid Karzai International Airport to enable the safe departure of US and allied personnel from Afghanistan via civilian and military flights," said a joint statement issued by the US Department of State and the Defense Department.

Over the next 48 hours, we will have expanded our security presence to nearly 6,000 troops, with a mission focused solely on facilitating these efforts and will be taking over air traffic control," it said.

The Kabul international airport, which is closed to all commercial flights, reportedly is the only exit point for people leaving Afghanistan.

The joint statement said that from tomorrow and over the coming days, the US will transfer out of the country thousands of American citizens who have been living in Afghanistan, as well as locally employed staff of the US mission in Kabul and their families and other vulnerable Afghan nationals.

"We will accelerate the evacuation of thousands of Afghans eligible for US Special Immigrant Visas, nearly 2,000 of whom have already arrived in the United States over the past two weeks. For all categories, Afghans who have cleared security screening will continue to be transferred directly to the United States. And we will find additional locations for those yet to be screened," the statement said.

State Department Spokesperson Ned Price said that Blinken spoke separately with his counterparts from Australia, France, Germany and Norway about developments in Afghanistan, including the security situation.

"They also discussed our efforts to bring our citizens to safety and assist vulnerable Afghans," he said.

Price also said that the safe evacuation of all American Embassy personnel is now complete.

"We can confirm that the safe evacuation of all Embassy personnel is now complete. All Embassy personnel are located on the premises of Hamid Karzai International Airport, whose perimeter is secured by the US Military," he said.

In a joint statement, more than 60 countries led by the US said that given the deteriorating security situation, they support and are working to secure and call on all parties to respect and facilitate the safe and orderly departure of foreign nationals and Afghans who wish to leave the country.

Those in positions of power and authority across Afghanistan bear responsibility and accountability for the protection of human life and property, and for the immediate restoration of security and civil order, the joint statement said.

Afghans and international citizens who wish to depart must be allowed to do so; roads, airports and border crossing must remain open, and calm must be maintained. The Afghan people deserve to live in safety, security and dignity. We in the international community stand ready to assist them, they said.

The Taliban on Sunday seized the last major city outside of Kabul held by the country's central government, cutting off the Afghan capital to the east.

The collapse of Jalalabad leaves Afghanistan's central government in control of just Kabul and six other provincial capitals out of the country's 34.

US President Joe Biden in April announced that all American troops would be withdrawn from Afghanistan by September 11 this year, thus bringing to end the country's longest war, spanning across two decades.

Since the US-led invasion that ousted the Taliban after the September 11, 2001 attacks, America has spent more than USD 1 trillion in fighting and rebuilding in Afghanistan.

About 2,400 US soldiers have been killed, along with tens of thousands of Afghan troops, Taliban insurgents and Afghan civilians.

PTI