A blast struck Thursday evening outside Kabul's main airport, where thousands of Afghans have converged in an attempt to catch one of the remaining flights out of the Taliban-controlled country.
Dozens of people were killed and many others were injured, among them 12 US marines.
The spokesman for the Taliban's political office in Doha, Suhail Shaheen, said the Taliban strongly condemn this atrocious incident and will take every step to bring the culprits to justice.
The US Department of Defence confirmed that 12 US soldiers were killed in the attack.
US General Kenneth McKenzie, who heads US Central Command Centcom, said this in a video call with journalists at the Pentagon on Thursday. Fifteen US soldiers were injured, he said.
US forces are continuing the evacuation mission in Kabul even after the devastating terrorist attack at the Afghan capital's airport, McKenzie said.
Another explosion occurred at a hotel nearby.
The US State Department on Twitter described the airport explosion as "large" and said there were also reports of gunfire in the vicinity.
Western governments had raised increasing alarm over the past 24 hours about the risk of terrorist attacks on the site.
The United States, Australia, Germany, Britain and others had warned their citizens against traveling to the airport, saying there was solid intelligence an attack could be imminent.
The Islamic State affiliate in Afghanistan called Islamic State Khorasan, or ISIS-K, has been singled out as the main threat to the evacuation operation. There are fears the group could exploit the chaos at the airport to target foreign troops and innocent civilians.
Desperation was growing at the airport as a Tuesday deadline to end the evacuation of foreigners and Afghans who worked with Western countries for the past two decades closes in.
Citing the security risks, several European countries announced an end to their military evacuations from the airport on Thursday, including the Netherlands, Belgium, Poland and Denmark.
Canada also said its mission was over after having helped 3,700 people leave.
"This is a painful moment," the Dutch government said in a letter to parliament, quoted by the ANP news agency.
People left behind
Despite all efforts, people who were supposed to be flown out are now being left behind in Afghanistan, the letter said, citing security concerns for the quick withdrawal.
The last four German flights took off on Thursday. The Defence Ministry said on Twitter they were "evacuating up to the last second."
France will end its operations on Friday, Prime Minister Jean Castex told broadcaster RTL. According to the latest information from the Foreign Ministry, France has flown more than 2,000 Afghans to France.
International forces are largely dependent on the thousands of US troops securing the Kabul airport.
Earlier this week, US President Joe Biden confirmed his intention to withdraw his troops by August 31 - this coming Tuesday - despite coming under pressure from US allies to extend it.
On Wednesday, US Secretary of State Antony Blinken said up to 1,500 Americans may still be awaiting an airlift, with thousands more Afghans also aiming to grab the remaining seats.
The White House on Thursday put the total number of evacuees on US and coalition flights at more 95,000 people, including some 13,000 in the past 24 hours.
The Pentagon rejected US media reports that its rescue missions would end within 36 hours, which would be several days before the Tuesday deadline.
One witness outside the airport said he went to the facility's eastern entrance for a third day in a row on Thursday in spite of the risks.
He said he had never seen so many people there before, describing the crowd as so packed it was like "bricks in a wall."
He said at one point he was about 200 metres from the entrance but it was impossible to move even a metre closer. He feared his child or his wife could be trampled to death, a fate others have suffered.
Even before the blast on Thursday, the Russian ambassador in Afghanistan put the number of people who have died in the mayhem at the airport in recent days at around 50.
"There is chaos at Kabul airport. The United States cannot secure anything there," Dmitriy Zhirnov told Russian state television. "There were casualties. About 50 ordinary people have died."
Qatar said on Thursday it had facilitated the evacuation of more than 40,000 people from Afghanistan to the Gulf emirate amid stepped-up evacuations from the country.
Most evacuees are transiting in Qatar, where they are hosted temporarily before departing on flights to other destinations, the Qatari Foreign Ministry said.