Pentagon officials also said they believe the attack outside Kabul airport was a result of one explosion, not two.
Condemnation and condolences have poured in from world leaders following the twin blasts outside Kabul’s airport that killed at least 110 people with dozens of others wounded.
Thursday’s attack was claimed by an offshoot of the armed group ISIL (ISIS) in Afghanistan, the Islamic State in Khorasan Province, ISKP (ISIS-K), which said its suicide bombers singled out “translators and collaborators with the American army”.
At least 13 US soldiers were among scores of people killed.
US President Joe Biden pledged to retaliate against the attack and confirmed the suicide bombings were carried out by ISKP. “We will hunt you down and make you pay. I will defend our interests in our people with every measure at my command,” he said.
“To those who carried out this attack, as well as anyone who wishes America harm, know this: We will not forgive; we will not forget.”
He called the slain American soldiers “heroes who had been engaged in a dangerous, selfless mission to safe the lives of others”.
“Our hearts ache … for all those Afghan families who lost loved ones, including small children, or who have been wounded in this vicious attack,” Biden said.
“I have also ordered my commanders to develop operational plans to strike ISIS-K assets, leadership and facilities. We will respond with force and precision on our time, at the place we choose and the moment of our choosing.”
NATO Secretary-General Jens Stoltenberg also expressed anger and sorrow.
“I strongly condemn the horrific terrorist attack outside Kabul airport. My thoughts are with all those affected and their loved ones,” he said on Twitter.
“Our priority remains to evacuate as many people to safety as quickly as possible,” added Stoltenberg.
The UK’s defence ministry said on Twitter there were no reports of British military or government casualties from the blasts.
Prime Minister Boris Johnson called an emergency meeting on Friday and said British evacuation efforts would continue despite the “barbaric” attacks.
“Clearly what this attack shows is the importance of continuing that work in as fast and as efficient a manner as possible in the hours that remain to us,” Johnson said.
Britain’s defence ministry said on Friday that British forces have entered the final stages of evacuating people from Kabul’s airport and processing facilities have closed.
The secretary of state for transport, meanwhile, issued a notice advising airlines to avoid Afghan airspace under 7,600 metres (25,000 feet).
Pakistan’s Foreign Affairs spokesman Asim Iftikhar Ahmad denounced the “heinous” attack at Kabul airport.
“We condemn terrorism in all forms and manifestations, convey our condolences to bereaved families and pray for early recovery of the injured,” he said on Twitter.
“Today’s attacks reinforce the need for the world to stand unitedly against terrorism and all those who provide sanctuaries to terrorists,” a statement from India’s external affairs ministry said.
Turkey’s foreign ministry deplored “this heinous attack in the strongest terms, offer our condolences to the relatives of those who lost their lives and wish a speedy recovery to the wounded”.
Egypt’s foreign ministry decried the “gruesome terrorism”.
Israeli Prime Minister Naftali Bennett, who is scheduled to meet with Biden in Washington on Friday, expressed his condolences on Twitter “over the loss of American lives in Kabul”.
“Israel stands with the United States in these difficult times, just as America has always stood with us,” he said.
In a statement, Qatar’s foreign ministry strongly condemned the attacks and conveyed condolences to the relatives of those who lost their lives and wished a speedy recovery to the injured.
On Twitter, Jordan’s Foreign Minister Ayman Safadi “strongly condemned” the attacks.
“Our thoughts and prayers are with victims of these horrific crimes. Terrorism remains a dangerous threat that dictates continuation of global efforts to defeat it & protect the innocent form its crimes. Deepest condolences,” he said.
The ministry of foreign affairs also decried “a heinous terrorist act that contradicts all moral and humanitarian values and principles”.
European Commission President Ursula von der Leyen denounced the “cowardly and inhuman attacks” on Twitter, adding “it is essential to do everything to ensure the safety of people at the airport”.
“The international community must work closely together to avoid a resurgence of terrorism in Afghanistan and beyond,” she added.
Beijing denounced the attack saying the blasts show “the security situation in Afghanistan is still complex and severe”, Chinese foreign ministry spokesman Zhao Lijian told reporters.
“China is shocked by and strongly condemns the explosions,” Zhao said, adding the ministry had not received any reports of Chinese casualties.
Canadian Prime Minister Justin Trudeau told reporters it had been “a very difficult day, not just for Afghans but for people around the world, including in Canada, who have long been deeply committed to the Afghan people and a better future for Afghanistan”.
“Our hearts break for the people of Afghanistan and the loved ones of the victims, including the brave women and men of our allies,” he said.
In a statement, New Zealand Prime Minister Jacinda Ardern said: “Our thoughts and condolences are with all of those in Afghanistan who have lost lives or suffered injuries, including US forces, our other partners on the ground, and the families and friends of all who have been affected by this appalling attack.”
She added New Zealand’s final Kabul evacuation flight was completed ahead of the explosions, with all the evacuees taken to the United Arab Emirates.
French President Emmanuel Macron said France’s ambassador to Afghanistan would leave the country and work from Paris. He said France shares the grief of the victims’ families.
On Twitter, French defence minister Florence Parly offered her condolences to her US counterpart Lloyd Austin over the “horrendous attack”.
“My thoughts are with the families and loved ones of the US Marines who lost their lives while helping those who wished to flee the terror. France stands with the United States,” Parly added.
Spain’s Prime Minister Pedro Sanchez said on Twitter, “Our heartfelt solidarity with the victims. The international community stands with the Afghan people, ensuring their rights and dignity.”
Noting Spain was working to evacuate “as many people as possible”, Sanchez said “enormous work” is being done by all the personnel involved in the evacuations from Afghanistan on a “particularly difficult day”.
He added two more planes arrived in Spain, one with 241 people on board and another with 95 passengers.
Italian Prime Minister Mario Draghi denounced “this vile and horrible attack against defenceless people seeking liberty”.
Norwegian Foreign Affairs Minister Ine Eriksen Soreide tweeted: “Innocent civilians trying to leave the country have become victims of this terrible act of cruelty.”
President Andrzej Duda condemned the “act of cowardice”. “Poland stands with our US and Afghani friends,” he said.
Swedish Minister for Foreign Affairs Ann Linde paid tribute to the US service members: “We are grateful for all your efforts in making this historic evacuation operation possible.”
Condemning the “despicable terrorist attack”, Czech Foreign Minister Jakub Kulhanek said. “I mourn the death of Afghans and members of the US military.”
Ukrainian President Volodymyr Zelensky also decried the “terrible terrorist attack” in Kabul.
“Deepest condolences to the people of the US and Afghanistan, to the families of the victims. Wish speedy recovery to the wounded. Terrorism must be condemned by all parties in Afghanistan. We must work jointly to evacuate those who need help,” he said on Twitter.