The number of Americans killed in the ISIS attack outside Kabul’s international airport in Afghanistan rose to 13 in addition to 18 others injured.

The Defense Department confirmed the numbers at 7.00 p.m. Thursday, Aug. 26, saying that all of the injured are in “the process of being aeromedically evacuated from Afghanistan on specially equipped C-17s with embarked surgical units,” CBS News reported.

A Marine Corps spokesman said that ten of the U.S. deaths were Marines.

Thursday’s attacks marked one of the single deadliest days for U.S. forces in Afghanistan in the 20-years war.

CBS cited the Pentagon saying that a suicide bomber detonated an explosion that tore through a crowd waiting at an entrance to the Hamid Karzai International Airport in the capital of Afghanistan. Thousands of people were gathered there, desperately waiting to board flights out of the country after the Taliban took control.

Another explosion struck a nearby hotel, the Pentagon added. 

Meanwhile, the number of Afghan people dead in the attack climbed to 90 as of Thursday evening, with 150 more wounded, the news outlet cited an Afghan official reporting.

The Islamic State affiliate in Afghanistan, known as ISIS Khorasan, or ISIS-K, claimed responsibility for the attacks, targeting American troops and Afghan allies.

Addressing the nation at the White House later in the day, President Biden vowed to retaliate against the terrorists and continue the withdrawal process.

“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. We will hunt you down and make you pay,” Biden said. “Our mission will go on. America will not be intimidated.”

When asked whether he is responsible for the way events in Afghanistan have unfolded since the U.S.–backed Afghan government collapsed, Biden said, “I bear responsibility for fundamentally all that’s happened of late.”

Biden again sought to blame the previous administration for the deal it negotiated with the Taliban.

The “reason why there were no attacks on Americans … was because the commitment was made by President Trump, ‘I will be out by May 1, in the meantime you agree not to attack any Americans.’ That was the deal,'” Biden said.

According to Gen. Frank McKenzie, head of U.S. Central Command, the United States officials were bracing for more attacks, New York Post reported.

“The threat from ISIS is completely real. We expect those attacks to continue and we are doing everything we can to be prepared for those attacks,” McKenzie said at a briefing. “That includes reaching out to the Taliban … to make sure they know what we expect them to do to protect us.”

Asked whether the U.S. military trusted the Taliban, McKenzie said that the group and the U.S. share “the common goal” of getting Western troops out by next week.

According to the White House, the United States has helped more than 100,000 people leave Afghanistan since Aug. 14.