U.S. forces were on alert for more attacks on Friday after an ISIS-K suicide bombing outside Kabul airport killed at least 92 people, including 13 U.S. troops. 

The White House said the next few days of the ongoing U.S. evacuation operation are likely to be the most dangerous. The Pentagon said it has taken about 111,000 people out of Afghanistan in the past two weeks.

Pentagon spokesman John Kirby said the U.S. believes there are still "specific, credible" threats against the airport after the bombing at one of the airport's gates. 

"We certainly are prepared and would expect future attempts," Kirby told reporters in Washington. "We're monitoring these threats, very, very specifically, virtually in real time." 

U.S. and allied forces are racing to complete evacuations of their citizens and their Afghan partners and to withdraw troops from Afghanistan by an August 31 deadline set by President Joe Biden after two decades of American military presence there. 

About 4,200 people were evacuated from Kabul during a 12-hour period on Friday, the White House said. Earlier in the day U.S. officials said a total of approximately 5,100 Americans had been evacuated, with about 500 more waiting to leave. 

Crowds of people have gathered outside the airport to try to get onto evacuation flights since the Taliban took control of Afghanistan on August 15. 

Taliban forces have taken up positions outside the Kabul airport and are ready to take full control as early as this weekend, as soon as U.S. forces leave, two senior Taliban figures said.  

Kirby disputed the Taliban account, telling reporters that the military section of the airport remains under U.S. control. 

"They are not in charge of any of the gates. They are not in charge of any of the airport operations. That is still under U.S. military control," Kirby said. 

The U.S. expects that some ongoing engagement with the Taliban will be necessary after the withdrawal to facilitate further evacuations, White House Press Secretary Jen Psaki said. 

"The reality is, the Taliban control large swathes of Afghanistan, including the areas surrounding the perimeter of the airport," she told reporters. "So by necessity, that is our option." 

Single suicide bomber 

ISIS-K, an affiliate of the Islamic State terrorist organization, has claimed responsibility for the attack, which the Pentagon said on Friday was carried out by one suicide bomber at an airport gate, not two as it earlier stated. 

The attack was the deadliest incident for U.S. troops in Afghanistan in a decade, according to reports. 

The number of Afghans killed has risen to 79, a hospital official told Reuters on Friday, adding that more than 120 were wounded. A Taliban official said the dead included 28 Taliban members, although a spokesman later denied any Taliban fighters had been killed. 

Biden said on Thursday he has ordered the Pentagon to plan how to strike ISIS-K. Asked on Friday if Biden sought to capture and put on trial those responsible, Psaki said: "I think he made it clear yesterday that he does not want them to live on the earth anymore." 

Biden was already facing strong criticism at home and abroad for the chaos surrounding the troop withdrawal and evacuations. 

Read more:

China condemns ISIL over Kabul airport attack, urges Taliban to live up to its anti-terrorism promise

Australia ends Afghanistan evacuation efforts ahead of Kabul blast

Most countries finish evacuations  

Most of the more than 20 allied countries involved in airlifting their citizens and Afghans out of Kabul said they had completed evacuations by Friday. 

British Defense Minister Ben Wallace said that Britain will not accept any more people for flights out of Kabul beyond those 1,000 people already inside the airport, after it shut its processing center and entered the final stages of its evacuation from Afghanistan. 

France has finished its evacuation operation from Kabul, Defense Minister Florence Parly said on Twitter, adding that nearly 3,000 people, including more than 2,600 Afghans, had been brought to France during the operation.  

Turkey has evacuated all troops and civilians from Afghanistan aside from a small "technical group" left behind, President Tayyip Erdogan also said on Friday, adding that a battle of "terrorist organizations" had taken hold in the country. 

Afghans will be able to travel freely in future: Taliban 

Afghans with valid documents will be able to travel in the future at any time, a senior Taliban official said on Friday in a televised address aimed at calming fears that the group planned harsh restrictions on freedom. 

"The Afghan borders will be open and people will be able to travel at any time into and out of Afghanistan," Sher Mohammad Abbas Stanikzai, deputy head of the group's political commission said. 

The message came as thousands have struggled to get onto the last flights leaving Kabul airport before August 31. 

Calling on Afghans to unite to rebuild their country, Stanikzai said that trained and educated people should come back to work. 

"The ground is prepared for the doctors, engineers and teachers that Afghanistan needs and for people from every profession, whether civilian or military. All are invited to start their work," he said. 

Coming after a separate statement calling on female health staff to return to work, the message underlined efforts by the Taliban to reassure Afghans and the international community that they do not plan a return to their previous harsh rule. 

Stanikzai also reiterated that the Taliban welcomed help from countries that wanted to play a positive role in Afghanistan, although he said they would not accept interference in its internal affairs. 

(With input from Reuters, Xinhua)

(Cover: In this image provided by the U.S. Army, a paratrooper assigned to the 1st Brigade Combat Team, 82nd Airborne Division monitors security during evacuations at Hamid Karzai International Airport in Kabul, Afghanistan, August 25, 2021. /CFP)