(CNN) — President Joe Biden plans to contact the families of the 13 US service members who were killed in Thursday’s suicide attacks outside of Kabul’s international airport, according to a senior White House official.

Planning is underway for the President to make those calls, but the White House is first working to ensure all of the next of kin notifications have taken place. The official said the next of kin notifications are “still ongoing.”

Biden called the troops “heroes” in remarks at the White House on Thursday and said he was “outraged as well as heartbroken.”

“We will not forgive. We will not forget. We will hunt you down and make you pay,” the President warned those who carried out the attacks.

ISIS in Khorasan, known as ISIS-K, has claimed that an ISIS militant carried out the suicide attacks, but provided no evidence to support the claim. US officials have said the group was likely behind the bombings.

Biden addressed the families of the fallen US service members on Thursday, saying “my heart aches for you.”

“We have some sense, like many of you do, what the families of these brave heroes are feeling today. You get this feeling like you’re being sucked into a black hole in the middle of your chest. There’s no way out,” Biden said in remarks at the White House.

He continued: “My heart aches for you and I know this, we have a continuing obligation, a sacred obligation to all of you, to the families of those heroes. That obligation is not temporary, it lasts forever.”

Biden’s son, Beau, an Iraq War veteran who served as the attorney general of Delaware, died at the age of 46 after battling brain cancer. Biden often speaks about his son and his service.

In addition to the 13 US service members who were killed, 18 were injured in the bombings, according to the head of the US Central Command. More than 90 Afghans were killed and at least 150 were wounded, according to Afghanistan’s Ministry of Public Health.

The attacks came as the US and other countries race to complete a massive evacuation of their citizens and Afghan allies by August 31 following the Taliban takeover of the country.

In the days leading up to the bombings, Biden had spoken about the risk of a terror attacks as one of the reasons for sticking with the August 31 deadline for withdrawing troops. The President had also promised a swift and forceful response to any disruption to the operation.

Biden and his team are now bracing for the possibility of another terrorist attacks in the final days of the evacuation operation.

“The threat is still out there,” a senior White House official said. “It’s still heightened.”

Biden plans to receive regular updates throughout the day on Friday on the state of the evacuation mission and the ongoing terrorist threat in Kabul, beginning with his daily intelligence briefing in the morning.

The President will then meet with his national security team in the Situation Room at the White House to discuss Afghanistan, as he has every day this week.

The official said Biden was “solemn and serious” on Thursday as updates on the attacks filtered in.

The-CNN-Wire
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